6404631 has 16 divisors (see below), whose sum is σ = 9335808. Its totient is φ = 3888000.

The previous prime is 6404623. The next prime is 6404639. The reversal of 6404631 is 1364046.

It is an interprime number because it is at equal distance from previous prime (6404623) and next prime (6404639).

It is not a de Polignac number, because 6404631 - 2³ = 6404623 is a prime.

It is a super-2 number, since 2×6404631² = 82038596492322, which contains 22 as substring.

6404631 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6404639) 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, 445 + ... + 3606.

It is an arithmetic number, because the mean of its divisors is an integer number (583488).

Almost surely, 2^6404631 is an apocalyptic number.

6404631 is a deficient number, since it is larger than the sum of its proper divisors (2931177).

6404631 is a wasteful number, since it uses less digits than its factorization.

6404631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4102.

The product of its (nonzero) digits is 1728, while the sum is 24.

The square root of 6404631 is about 2530.7372443618. The cubic root of 6404631 is about 185.7083242099.

Adding to 6404631 its reverse (1364046), we get a palindrome (7768677).

The spelling of 6404631 in words is "six million, four hundred four thousand, six hundred thirty-one".