251920422 has 32 divisors (see below), whose sum is σ = 602888160. Its totient is φ = 77513760.

The previous prime is 251920393. The next prime is 251920429. The reversal of 251920422 is 224029152.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251920429) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 178729 + ... + 180132.

It is an arithmetic number, because the mean of its divisors is an integer number (18840255).

Almost surely, 2^251920422 is an apocalyptic number.

251920422 is an abundant number, since it is smaller than the sum of its proper divisors (350967738).

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

251920422 is a wasteful number, since it uses less digits than its factorization.

251920422 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 358885 (or 358879 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 251920422 is about 15872.0011970766. The cubic root of 251920422 is about 631.5694655616.

Adding to 251920422 its reverse (224029152), we get a palindrome (475949574).

The spelling of 251920422 in words is "two hundred fifty-one million, nine hundred twenty thousand, four hundred twenty-two".