1866488400 has 360 divisors, whose sum is σ = 7730130240. Its totient is φ = 426504960.

The previous prime is 1866488357. The next prime is 1866488413. The reversal of 1866488400 is 48846681.

1866488400 is a `hidden beast` number, since 186 + 64 + 8 + 8 + 400 = 666.

It is a tau number, because it is divible by the number of its divisors (360).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 527437 + ... + 530963.

It is an arithmetic number, because the mean of its divisors is an integer number (21472584).

Almost surely, 2^1866488400 is an apocalyptic number.

1866488400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1866488400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3865065120).

1866488400 is an abundant number, since it is smaller than the sum of its proper divisors (5863641840).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1866488400 is a wasteful number, since it uses less digits than its factorization.

1866488400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3568 (or 3544 counting only the distinct ones).

The product of its (nonzero) digits is 294912, while the sum is 45.

The square root of 1866488400 is about 43202.8749043394. The cubic root of 1866488400 is about 1231.2373034155.

The spelling of 1866488400 in words is "one billion, eight hundred sixty-six million, four hundred eighty-eight thousand, four hundred".