20331431 has 4 divisors (see below), whose sum is σ = 20576472. Its totient is φ = 20086392.

The previous prime is 20331419. The next prime is 20331461. The reversal of 20331431 is 13413302.

It is a happy number.

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 20331431 - 2¹⁰ = 20330407 is a prime.

It is a super-2 number, since 2×20331431² = 826734173015522, 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 (20331461) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 122396 + ... + 122561.

It is an arithmetic number, because the mean of its divisors is an integer number (5144118).

Almost surely, 2^20331431 is an apocalyptic number.

20331431 is a deficient number, since it is larger than the sum of its proper divisors (245041).

20331431 is an equidigital number, since it uses as much as digits as its factorization.

20331431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 245040.

The product of its (nonzero) digits is 216, while the sum is 17.

The square root of 20331431 is about 4509.0388110993. The cubic root of 20331431 is about 272.9329581739.

Adding to 20331431 its reverse (13413302), we get a palindrome (33744733).

The spelling of 20331431 in words is "twenty million, three hundred thirty-one thousand, four hundred thirty-one".