251855156 has 24 divisors (see below), whose sum is σ = 504047040. Its totient is φ = 107865792.

The previous prime is 251855143. The next prime is 251855159. The reversal of 251855156 is 651558152.

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251855159) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 76880 + ... + 80088.

It is an arithmetic number, because the mean of its divisors is an integer number (21001960).

Almost surely, 2^251855156 is an apocalyptic number.

It is an amenable number.

251855156 is an abundant number, since it is smaller than the sum of its proper divisors (252191884).

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

251855156 is a wasteful number, since it uses less digits than its factorization.

251855156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6023 (or 6021 counting only the distinct ones).

The product of its digits is 60000, while the sum is 38.

The square root of 251855156 is about 15869.9450534651. The cubic root of 251855156 is about 631.5149198012.

The spelling of 251855156 in words is "two hundred fifty-one million, eight hundred fifty-five thousand, one hundred fifty-six".