21401552631 has 16 divisors (see below), whose sum is σ = 28689791328. Its totient is φ = 14190556800.

The previous prime is 21401552597. The next prime is 21401552651. The reversal of 21401552631 is 13625510412.

It is a de Polignac number, because none of the positive numbers 2^k-21401552631 is a prime.

It is a super-2 number, since 2×21401552631² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21401552651) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3437101 + ... + 3443321.

It is an arithmetic number, because the mean of its divisors is an integer number (1793111958).

Almost surely, 2^21401552631 is an apocalyptic number.

21401552631 is a deficient number, since it is larger than the sum of its proper divisors (7288238697).

21401552631 is a wasteful number, since it uses less digits than its factorization.

21401552631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12242.

The product of its (nonzero) digits is 7200, while the sum is 30.

The spelling of 21401552631 in words is "twenty-one billion, four hundred one million, five hundred fifty-two thousand, six hundred thirty-one".