21214036536631 has 4 divisors (see below), whose sum is σ = 21218333490432. Its totient is φ = 21209739582832.

The previous prime is 21214036536617. The next prime is 21214036536677. The reversal of 21214036536631 is 13663563041212.

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 21214036536631 - 2¹¹ = 21214036534583 is a prime.

It is a super-2 number, since 2×21214036536631² (a number of 27 digits) 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 (21214036536131) 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, 2148469495 + ... + 2148479368.

It is an arithmetic number, because the mean of its divisors is an integer number (5304583372608).

Almost surely, 2^{21214036536631} is an apocalyptic number.

21214036536631 is a deficient number, since it is larger than the sum of its proper divisors (4296953801).

21214036536631 is an equidigital number, since it uses as much as digits as its factorization.

21214036536631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4296953800.

The product of its (nonzero) digits is 466560, while the sum is 43.

Adding to 21214036536631 its reverse (13663563041212), we get a palindrome (34877599577843).

The spelling of 21214036536631 in words is "twenty-one trillion, two hundred fourteen billion, thirty-six million, five hundred thirty-six thousand, six hundred thirty-one".