21101647631 has 2 divisors, whose sum is σ = 21101647632. Its totient is φ = 21101647630.

The previous prime is 21101647607. The next prime is 21101647639. The reversal of 21101647631 is 13674610112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21101647631 - 2¹⁴ = 21101631247 is a prime.

It is a super-2 number, since 2×21101647631² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21101647639) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10550823815 + 10550823816.

It is an arithmetic number, because the mean of its divisors is an integer number (10550823816).

Almost surely, 2^21101647631 is an apocalyptic number.

21101647631 is a deficient number, since it is larger than the sum of its proper divisors (1).

21101647631 is an equidigital number, since it uses as much as digits as its factorization.

21101647631 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6048, while the sum is 32.

The spelling of 21101647631 in words is "twenty-one billion, one hundred one million, six hundred forty-seven thousand, six hundred thirty-one".