20172631 has 8 divisors (see below), whose sum is σ = 20638800. Its totient is φ = 19710720.

The previous prime is 20172617. The next prime is 20172637. The reversal of 20172631 is 13627102.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20172631 - 2¹³ = 20164439 is a prime.

It is a super-2 number, since 2×20172631² = 813870082924322, 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 (20172637) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9735 + ... + 11623.

It is an arithmetic number, because the mean of its divisors is an integer number (2579850).

Almost surely, 2^20172631 is an apocalyptic number.

20172631 is a deficient number, since it is larger than the sum of its proper divisors (466169).

20172631 is a wasteful number, since it uses less digits than its factorization.

20172631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2129.

The product of its (nonzero) digits is 504, while the sum is 22.

The square root of 20172631 is about 4491.3952175243. The cubic root of 20172631 is about 272.2205130409.

Adding to 20172631 its reverse (13627102), we get a palindrome (33799733).

The spelling of 20172631 in words is "twenty million, one hundred seventy-two thousand, six hundred thirty-one".