402990881 has 2 divisors, whose sum is σ = 402990882. Its totient is φ = 402990880.

The previous prime is 402990877. The next prime is 402990901. The reversal of 402990881 is 188099204.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 233600656 + 169390225 = 15284^2 + 13015^2 .

It is a cyclic number.

It is not a de Polignac number, because 402990881 - 2² = 402990877 is a prime.

It is a super-2 number, since 2×402990881² = 324803300338312322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (402990781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 201495440 + 201495441.

It is an arithmetic number, because the mean of its divisors is an integer number (201495441).

Almost surely, 2^402990881 is an apocalyptic number.

It is an amenable number.

402990881 is a deficient number, since it is larger than the sum of its proper divisors (1).

402990881 is an equidigital number, since it uses as much as digits as its factorization.

402990881 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 41472, while the sum is 41.

The square root of 402990881 is about 20074.6327737271. The cubic root of 402990881 is about 738.6381581961.

The spelling of 402990881 in words is "four hundred two million, nine hundred ninety thousand, eight hundred eighty-one".