21298177631 has 2 divisors, whose sum is σ = 21298177632. Its totient is φ = 21298177630.

The previous prime is 21298177619. The next prime is 21298177673. The reversal of 21298177631 is 13677189212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21298177631 - 2²⁶ = 21231068767 is a prime.

It is a super-2 number, since 2×21298177631² (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 (21298077631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10649088815 + 10649088816.

It is an arithmetic number, because the mean of its divisors is an integer number (10649088816).

Almost surely, 2^21298177631 is an apocalyptic number.

21298177631 is a deficient number, since it is larger than the sum of its proper divisors (1).

21298177631 is an equidigital number, since it uses as much as digits as its factorization.

21298177631 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 254016, while the sum is 47.

The spelling of 21298177631 in words is "twenty-one billion, two hundred ninety-eight million, one hundred seventy-seven thousand, six hundred thirty-one".