402631279 has 4 divisors (see below), whose sum is σ = 402748776. Its totient is φ = 402513784.

The previous prime is 402631259. The next prime is 402631291. The reversal of 402631279 is 972136204.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-402631279 is a prime.

It is a super-2 number, since 2×402631279² = 324223893658351682, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (402631219) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53449 + ... + 60514.

It is an arithmetic number, because the mean of its divisors is an integer number (100687194).

Almost surely, 2^402631279 is an apocalyptic number.

402631279 is a deficient number, since it is larger than the sum of its proper divisors (117497).

402631279 is a wasteful number, since it uses less digits than its factorization.

402631279 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117496.

The product of its (nonzero) digits is 18144, while the sum is 34.

The square root of 402631279 is about 20065.6741476582. The cubic root of 402631279 is about 738.4183891173.

The spelling of 402631279 in words is "four hundred two million, six hundred thirty-one thousand, two hundred seventy-nine".