21670357828211 has 2 divisors, whose sum is σ = 21670357828212. Its totient is φ = 21670357828210.

The previous prime is 21670357828153. The next prime is 21670357828271. The reversal of 21670357828211 is 11282875307612.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21670357828211 is a prime.

It is not a weakly prime, because it can be changed into another prime (21670357828271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10835178914105 + 10835178914106.

It is an arithmetic number, because the mean of its divisors is an integer number (10835178914106).

Almost surely, 2^{21670357828211} is an apocalyptic number.

21670357828211 is a deficient number, since it is larger than the sum of its proper divisors (1).

21670357828211 is an equidigital number, since it uses as much as digits as its factorization.

21670357828211 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2257920, while the sum is 53.

The spelling of 21670357828211 in words is "twenty-one trillion, six hundred seventy billion, three hundred fifty-seven million, eight hundred twenty-eight thousand, two hundred eleven".