1917990240 has 192 divisors, whose sum is σ = 6400912896. Its totient is φ = 481738752.

The previous prime is 1917990233. The next prime is 1917990251. The reversal of 1917990240 is 420997191.

It is a junction number, because it is equal to n+sod(n) for n = 1917990192 and 1917990201.

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 31 ways as a sum of consecutive naturals, for example, 738384 + ... + 740976.

It is an arithmetic number, because the mean of its divisors is an integer number (33338088).

Almost surely, 2^1917990240 is an apocalyptic number.

1917990240 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 1917990240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3200456448).

1917990240 is an abundant number, since it is smaller than the sum of its proper divisors (4482922656).

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

1917990240 is a wasteful number, since it uses less digits than its factorization.

1917990240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2701 (or 2693 counting only the distinct ones).

The product of its (nonzero) digits is 40824, while the sum is 42.

The square root of 1917990240 is about 43794.8654524706. The cubic root of 1917990240 is about 1242.4591848968.

The spelling of 1917990240 in words is "one billion, nine hundred seventeen million, nine hundred ninety thousand, two hundred forty".