636426999 has 12 divisors (see below), whose sum is σ = 989997736. Its totient is φ = 391647312.

The previous prime is 636426971. The next prime is 636427007. The reversal of 636426999 is 999624636.

It is not a de Polignac number, because 636426999 - 2⁷ = 636426871 is a prime.

It is a super-3 number, since 3×636426999³ (a number of 27 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (636426919) 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, 2719657 + ... + 2719890.

Almost surely, 2^636426999 is an apocalyptic number.

636426999 is a deficient number, since it is larger than the sum of its proper divisors (353570737).

636426999 is a wasteful number, since it uses less digits than its factorization.

636426999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5439566 (or 5439563 counting only the distinct ones).

The product of its digits is 3779136, while the sum is 54.

The square root of 636426999 is about 25227.5048112175. The cubic root of 636426999 is about 860.1671745499.

The spelling of 636426999 in words is "six hundred thirty-six million, four hundred twenty-six thousand, nine hundred ninety-nine".