21463220231 has 6 divisors (see below), whose sum is σ = 21677841696. Its totient is φ = 21250703000.

The previous prime is 21463220227. The next prime is 21463220269. The reversal of 21463220231 is 13202236412.

It is not a de Polignac number, because 21463220231 - 2² = 21463220227 is a prime.

It is a super-2 number, since 2×21463220231² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21463220231.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21463220731) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1041815 + ... + 1062216.

It is an arithmetic number, because the mean of its divisors is an integer number (3612973616).

Almost surely, 2^21463220231 is an apocalyptic number.

21463220231 is a deficient number, since it is larger than the sum of its proper divisors (214621465).

21463220231 is an equidigital number, since it uses as much as digits as its factorization.

21463220231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2104233 (or 2104132 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 26.

Adding to 21463220231 its reverse (13202236412), we get a palindrome (34665456643).

The spelling of 21463220231 in words is "twenty-one billion, four hundred sixty-three million, two hundred twenty thousand, two hundred thirty-one".