21172580699 has 2 divisors, whose sum is σ = 21172580700. Its totient is φ = 21172580698.

The previous prime is 21172580629. The next prime is 21172580711. The reversal of 21172580699 is 99608527112.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21172580699 is a prime.

It is not a weakly prime, because it can be changed into another prime (21172580629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10586290349 + 10586290350.

It is an arithmetic number, because the mean of its divisors is an integer number (10586290350).

Almost surely, 2^21172580699 is an apocalyptic number.

21172580699 is a deficient number, since it is larger than the sum of its proper divisors (1).

21172580699 is an equidigital number, since it uses as much as digits as its factorization.

21172580699 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 544320, while the sum is 50.

The spelling of 21172580699 in words is "twenty-one billion, one hundred seventy-two million, five hundred eighty thousand, six hundred ninety-nine".