164515352581 has 2 divisors, whose sum is σ = 164515352582. Its totient is φ = 164515352580.

The previous prime is 164515352569. The next prime is 164515352609. The reversal of 164515352581 is 185253515461.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 128920493025 + 35594859556 = 359055^2 + 188666^2 .

It is a cyclic number.

It is not a de Polignac number, because 164515352581 - 2¹⁹ = 164514828293 is a prime.

It is a super-2 number, since 2×164515352581² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (164515352501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82257676290 + 82257676291.

It is an arithmetic number, because the mean of its divisors is an integer number (82257676291).

Almost surely, 2^164515352581 is an apocalyptic number.

It is an amenable number.

164515352581 is a deficient number, since it is larger than the sum of its proper divisors (1).

164515352581 is an equidigital number, since it uses as much as digits as its factorization.

164515352581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 720000, while the sum is 46.

The spelling of 164515352581 in words is "one hundred sixty-four billion, five hundred fifteen million, three hundred fifty-two thousand, five hundred eighty-one".