20431631 has 16 divisors (see below), whose sum is σ = 24278400. Its totient is φ = 16984800.

The previous prime is 20431627. The next prime is 20431639. The reversal of 20431631 is 13613402.

It is a cyclic number.

It is not a de Polignac number, because 20431631 - 2² = 20431627 is a prime.

It is a super-2 number, since 2×20431631² = 834903090640322, 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 (20431639) 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, 4376 + ... + 7746.

It is an arithmetic number, because the mean of its divisors is an integer number (1517400).

Almost surely, 2^20431631 is an apocalyptic number.

20431631 is a deficient number, since it is larger than the sum of its proper divisors (3846769).

20431631 is a wasteful number, since it uses less digits than its factorization.

20431631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3430.

The product of its (nonzero) digits is 432, while the sum is 20.

The square root of 20431631 is about 4520.1361705152. The cubic root of 20431631 is about 273.3805915049.

The spelling of 20431631 in words is "twenty million, four hundred thirty-one thousand, six hundred thirty-one".