21151520015627 has 2 divisors, whose sum is σ = 21151520015628. Its totient is φ = 21151520015626.

The previous prime is 21151520015599. The next prime is 21151520015641. The reversal of 21151520015627 is 72651002515112.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21151520015627 is a prime.

It is not a weakly prime, because it can be changed into another prime (21151520215627) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10575760007813 + 10575760007814.

It is an arithmetic number, because the mean of its divisors is an integer number (10575760007814).

Almost surely, 2^{21151520015627} is an apocalyptic number.

21151520015627 is a deficient number, since it is larger than the sum of its proper divisors (1).

21151520015627 is an equidigital number, since it uses as much as digits as its factorization.

21151520015627 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 42000, while the sum is 38.

The spelling of 21151520015627 in words is "twenty-one trillion, one hundred fifty-one billion, five hundred twenty million, fifteen thousand, six hundred twenty-seven".