20257156 has 12 divisors (see below), whose sum is σ = 35481600. Its totient is φ = 10119560.

The previous prime is 20257121. The next prime is 20257163. The reversal of 20257156 is 65175202.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7245 + ... + 9643.

It is an arithmetic number, because the mean of its divisors is an integer number (2956800).

Almost surely, 2^20257156 is an apocalyptic number.

It is an amenable number.

20257156 is a deficient number, since it is larger than the sum of its proper divisors (15224444).

20257156 is a wasteful number, since it uses less digits than its factorization.

20257156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4514 (or 4512 counting only the distinct ones).

The product of its (nonzero) digits is 4200, while the sum is 28.

The square root of 20257156 is about 4500.7950408789. The cubic root of 20257156 is about 272.6001920941.

The spelling of 20257156 in words is "twenty million, two hundred fifty-seven thousand, one hundred fifty-six".