251246642 has 4 divisors (see below), whose sum is σ = 376869966. Its totient is φ = 125623320.

The previous prime is 251246609. The next prime is 251246669. The reversal of 251246642 is 246642152.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 244891201 + 6355441 = 15649^2 + 2521^2 .

It is a junction number, because it is equal to n+sod(n) for n = 251246599 and 251246608.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 62811659 + ... + 62811662.

Almost surely, 2^251246642 is an apocalyptic number.

251246642 is a deficient number, since it is larger than the sum of its proper divisors (125623324).

251246642 is a wasteful number, since it uses less digits than its factorization.

251246642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125623323.

The product of its digits is 23040, while the sum is 32.

The square root of 251246642 is about 15850.7615589914. The cubic root of 251246642 is about 631.0059029170.

Adding to 251246642 its reverse (246642152), we get a palindrome (497888794).

The spelling of 251246642 in words is "two hundred fifty-one million, two hundred forty-six thousand, six hundred forty-two".