251961428 has 24 divisors (see below), whose sum is σ = 455879424. Its totient is φ = 121723200.

The previous prime is 251961421. The next prime is 251961433. The reversal of 251961428 is 824169152.

It is a super-2 number, since 2×251961428² = 126969122399598368, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 251961391 and 251961400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251961421) 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, 105083 + ... + 107453.

It is an arithmetic number, because the mean of its divisors is an integer number (18994976).

Almost surely, 2^251961428 is an apocalyptic number.

It is an amenable number.

251961428 is a deficient number, since it is larger than the sum of its proper divisors (203917996).

251961428 is a wasteful number, since it uses less digits than its factorization.

251961428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3263 (or 3261 counting only the distinct ones).

The product of its digits is 34560, while the sum is 38.

The square root of 251961428 is about 15873.2929160902. The cubic root of 251961428 is about 631.6037313193.

The spelling of 251961428 in words is "two hundred fifty-one million, nine hundred sixty-one thousand, four hundred twenty-eight".