20091631 has 16 divisors (see below), whose sum is σ = 23554048. Its totient is φ = 16783200.

The previous prime is 20091619. The next prime is 20091649. The reversal of 20091631 is 13619002.

It is not a de Polignac number, because 20091631 - 2⁹ = 20091119 is a prime.

It is a super-2 number, since 2×20091631² = 807347272480322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20091691) 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, 89986 + ... + 90208.

It is an arithmetic number, because the mean of its divisors is an integer number (1472128).

Almost surely, 2^20091631 is an apocalyptic number.

20091631 is a deficient number, since it is larger than the sum of its proper divisors (3462417).

20091631 is a wasteful number, since it uses less digits than its factorization.

20091631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 502.

The product of its (nonzero) digits is 324, while the sum is 22.

The square root of 20091631 is about 4482.3689049430. The cubic root of 20091631 is about 271.8556715197.

The spelling of 20091631 in words is "twenty million, ninety-one thousand, six hundred thirty-one".