1564640 has 96 divisors (see below), whose sum is σ = 4644864. Its totient is φ = 483840.

The previous prime is 1564603. The next prime is 1564643. The reversal of 1564640 is 464651.

It is a happy number.

It is a hoax number, since the sum of its digits (26) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1564643) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12257 + ... + 12383.

It is an arithmetic number, because the mean of its divisors is an integer number (48384).

2^1564640 is an apocalyptic number.

1564640 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 1564640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2322432).

1564640 is an abundant number, since it is smaller than the sum of its proper divisors (3080224).

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

1564640 is a wasteful number, since it uses less digits than its factorization.

1564640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160 (or 152 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 1564640 is about 1250.8557071061. The cubic root of 1564640 is about 116.0926726739.

The spelling of 1564640 in words is "one million, five hundred sixty-four thousand, six hundred forty".