21707173511 has 2 divisors, whose sum is σ = 21707173512. Its totient is φ = 21707173510.

The previous prime is 21707173489. The next prime is 21707173517. The reversal of 21707173511 is 11537170712.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21707173511 - 2¹⁸ = 21706911367 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21707173517) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10853586755 + 10853586756.

It is an arithmetic number, because the mean of its divisors is an integer number (10853586756).

Almost surely, 2^21707173511 is an apocalyptic number.

21707173511 is a deficient number, since it is larger than the sum of its proper divisors (1).

21707173511 is an equidigital number, since it uses as much as digits as its factorization.

21707173511 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10290, while the sum is 35.

The spelling of 21707173511 in words is "twenty-one billion, seven hundred seven million, one hundred seventy-three thousand, five hundred eleven".