2158257564 has 72 divisors (see below), whose sum is σ = 5550068160. Its totient is φ = 707046912.

The previous prime is 2158257547. The next prime is 2158257611. The reversal of 2158257564 is 4657528512.

2158257564 is a `hidden beast` number, since 2 + 1 + 5 + 82 + 5 + 7 + 564 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 661024 + ... + 664280.

It is an arithmetic number, because the mean of its divisors is an integer number (77084280).

Almost surely, 2^2158257564 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2158257564, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2775034080).

2158257564 is an abundant number, since it is smaller than the sum of its proper divisors (3391810596).

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

2158257564 is a wasteful number, since it uses less digits than its factorization.

2158257564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3579 (or 3574 counting only the distinct ones).

The product of its digits is 672000, while the sum is 45.

The square root of 2158257564 is about 46457.0507458233. The cubic root of 2158257564 is about 1292.3131312009.

The spelling of 2158257564 in words is "two billion, one hundred fifty-eight million, two hundred fifty-seven thousand, five hundred sixty-four".