21267662651 has 2 divisors, whose sum is σ = 21267662652. Its totient is φ = 21267662650.

The previous prime is 21267662621. The next prime is 21267662707. The reversal of 21267662651 is 15626676212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21267662651 - 2³⁴ = 4087793467 is a prime.

It is not a weakly prime, because it can be changed into another prime (21267662621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10633831325 + 10633831326.

It is an arithmetic number, because the mean of its divisors is an integer number (10633831326).

Almost surely, 2^21267662651 is an apocalyptic number.

21267662651 is a deficient number, since it is larger than the sum of its proper divisors (1).

21267662651 is an equidigital number, since it uses as much as digits as its factorization.

21267662651 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 362880, while the sum is 44.

The spelling of 21267662651 in words is "twenty-one billion, two hundred sixty-seven million, six hundred sixty-two thousand, six hundred fifty-one".