21706117165147 has 2 divisors, whose sum is σ = 21706117165148. Its totient is φ = 21706117165146.

The previous prime is 21706117165141. The next prime is 21706117165169. The reversal of 21706117165147 is 74156171160712.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21706117165147 - 2¹⁵ = 21706117132379 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21706117165147.

It is not a weakly prime, because it can be changed into another prime (21706117165141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10853058582573 + 10853058582574.

It is an arithmetic number, because the mean of its divisors is an integer number (10853058582574).

Almost surely, 2^{21706117165147} is an apocalyptic number.

21706117165147 is a deficient number, since it is larger than the sum of its proper divisors (1).

21706117165147 is an equidigital number, since it uses as much as digits as its factorization.

21706117165147 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 493920, while the sum is 49.

The spelling of 21706117165147 in words is "twenty-one trillion, seven hundred six billion, one hundred seventeen million, one hundred sixty-five thousand, one hundred forty-seven".