21044202431 has 12 divisors (see below), whose sum is σ = 24533583408. Its totient is φ = 17998398432.

The previous prime is 21044202397. The next prime is 21044202433. The reversal of 21044202431 is 13420244012.

It is not a de Polignac number, because 21044202431 - 2⁶ = 21044202367 is a prime.

It is a super-2 number, since 2×21044202431² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21044202397 and 21044202406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21044202433) 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, 447491 + ... + 492276.

It is an arithmetic number, because the mean of its divisors is an integer number (2044465284).

Almost surely, 2^21044202431 is an apocalyptic number.

21044202431 is a deficient number, since it is larger than the sum of its proper divisors (3489380977).

21044202431 is an equidigital number, since it uses as much as digits as its factorization.

21044202431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 940238 (or 940231 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 23.

Adding to 21044202431 its reverse (13420244012), we get a palindrome (34464446443).

The spelling of 21044202431 in words is "twenty-one billion, forty-four million, two hundred two thousand, four hundred thirty-one".