164937776681 has 2 divisors, whose sum is σ = 164937776682. Its totient is φ = 164937776680.

The previous prime is 164937776629. The next prime is 164937776711. The reversal of 164937776681 is 186677739461.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 163748906281 + 1188870400 = 404659^2 + 34480^2 .

It is a cyclic number.

It is not a de Polignac number, because 164937776681 - 2²⁶ = 164870667817 is a prime.

It is a super-2 number, since 2×164937776681² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (164937773681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82468888340 + 82468888341.

It is an arithmetic number, because the mean of its divisors is an integer number (82468888341).

Almost surely, 2^164937776681 is an apocalyptic number.

It is an amenable number.

164937776681 is a deficient number, since it is larger than the sum of its proper divisors (1).

164937776681 is an equidigital number, since it uses as much as digits as its factorization.

164937776681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 64012032, while the sum is 65.

The spelling of 164937776681 in words is "one hundred sixty-four billion, nine hundred thirty-seven million, seven hundred seventy-six thousand, six hundred eighty-one".