20158431 has 4 divisors (see below), whose sum is σ = 26877912. Its totient is φ = 13438952.

The previous prime is 20158427. The next prime is 20158433. The reversal of 20158431 is 13485102.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20158431 - 2² = 20158427 is a prime.

It is a super-2 number, since 2×20158431² = 812724680763522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20158433) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3359736 + ... + 3359741.

It is an arithmetic number, because the mean of its divisors is an integer number (6719478).

Almost surely, 2^20158431 is an apocalyptic number.

20158431 is a deficient number, since it is larger than the sum of its proper divisors (6719481).

20158431 is an equidigital number, since it uses as much as digits as its factorization.

20158431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6719480.

The product of its (nonzero) digits is 960, while the sum is 24.

The square root of 20158431 is about 4489.8141386922. The cubic root of 20158431 is about 272.1566238594.

The spelling of 20158431 in words is "twenty million, one hundred fifty-eight thousand, four hundred thirty-one".