251773728 has 48 divisors (see below), whose sum is σ = 663235776. Its totient is φ = 83628800.

The previous prime is 251773727. The next prime is 251773733. The reversal of 251773728 is 827377152.

It is a tau number, because it is divible by the number of its divisors (48).

It is a super-2 number, since 2×251773728² = 126780020222035968, which contains 22 as substring.

It is a hoax number, since the sum of its digits (42) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 251773728.

It is not an unprimeable number, because it can be changed into a prime (251773727) 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, 23653 + ... + 32603.

It is an arithmetic number, because the mean of its divisors is an integer number (13817412).

Almost surely, 2^251773728 is an apocalyptic number.

It is an amenable number.

251773728 is an abundant number, since it is smaller than the sum of its proper divisors (411462048).

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

251773728 is a wasteful number, since it uses less digits than its factorization.

251773728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9257 (or 9249 counting only the distinct ones).

The product of its digits is 164640, while the sum is 42.

The square root of 251773728 is about 15867.3793677469. The cubic root of 251773728 is about 631.4468535092.

It can be divided in two parts, 2517 and 73728, that added together give a triangular number (76245 = T₃₉₀).

The spelling of 251773728 in words is "two hundred fifty-one million, seven hundred seventy-three thousand, seven hundred twenty-eight".