21627587129 has 2 divisors, whose sum is σ = 21627587130. Its totient is φ = 21627587128.

The previous prime is 21627587123. The next prime is 21627587147. The reversal of 21627587129 is 92178572612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20348451904 + 1279135225 = 142648^2 + 35765^2 .

It is a cyclic number.

It is not a de Polignac number, because 21627587129 - 2¹⁶ = 21627521593 is a prime.

It is not a weakly prime, because it can be changed into another prime (21627587123) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10813793564 + 10813793565.

It is an arithmetic number, because the mean of its divisors is an integer number (10813793565).

Almost surely, 2^21627587129 is an apocalyptic number.

It is an amenable number.

21627587129 is a deficient number, since it is larger than the sum of its proper divisors (1).

21627587129 is an equidigital number, since it uses as much as digits as its factorization.

21627587129 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 846720, while the sum is 50.

The spelling of 21627587129 in words is "twenty-one billion, six hundred twenty-seven million, five hundred eighty-seven thousand, one hundred twenty-nine".