20211431 has 4 divisors (see below), whose sum is σ = 20220552. Its totient is φ = 20202312.

The previous prime is 20211407. The next prime is 20211461. The reversal of 20211431 is 13411202.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 20211431 - 2¹⁴ = 20195047 is a prime.

It is a super-2 number, since 2×20211431² = 817003886135522, 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 (20211461) 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, 1136 + ... + 6458.

It is an arithmetic number, because the mean of its divisors is an integer number (5055138).

Almost surely, 2^20211431 is an apocalyptic number.

20211431 is a deficient number, since it is larger than the sum of its proper divisors (9121).

20211431 is an equidigital number, since it uses as much as digits as its factorization.

20211431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9120.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 20211431 is about 4495.7125130506. The cubic root of 20211431 is about 272.3949307357.

Adding to 20211431 its reverse (13411202), we get a palindrome (33622633).

The spelling of 20211431 in words is "twenty million, two hundred eleven thousand, four hundred thirty-one".