402401691 has 12 divisors (see below), whose sum is σ = 581467120. Its totient is φ = 268166160.

The previous prime is 402401683. The next prime is 402401693. The reversal of 402401691 is 196104204.

It is not a de Polignac number, because 402401691 - 2³ = 402401683 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (402401693) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 22605 + ... + 36273.

Almost surely, 2^402401691 is an apocalyptic number.

402401691 is a deficient number, since it is larger than the sum of its proper divisors (179065429).

402401691 is a wasteful number, since it uses less digits than its factorization.

402401691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16946 (or 16943 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 402401691 is about 20059.9524176903. The cubic root of 402401691 is about 738.2780090362.

Adding to 402401691 its reverse (196104204), we get a palindrome (598505895).

The spelling of 402401691 in words is "four hundred two million, four hundred one thousand, six hundred ninety-one".