20147831 has 12 divisors (see below), whose sum is σ = 22264200. Its totient is φ = 18218640.

The previous prime is 20147821. The next prime is 20147833. The reversal of 20147831 is 13874102.

It is not a de Polignac number, because 20147831 - 2²² = 15953527 is a prime.

It is a super-2 number, since 2×20147831² = 811870188009122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20147831.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20147833) 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, 32240 + ... + 32858.

It is an arithmetic number, because the mean of its divisors is an integer number (1855350).

Almost surely, 2^20147831 is an apocalyptic number.

20147831 is a deficient number, since it is larger than the sum of its proper divisors (2116369).

20147831 is a wasteful number, since it uses less digits than its factorization.

20147831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 910 (or 899 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 26.

The square root of 20147831 is about 4488.6335337160. The cubic root of 20147831 is about 272.1089123747.

The spelling of 20147831 in words is "twenty million, one hundred forty-seven thousand, eight hundred thirty-one".