156504640661 has 12 divisors (see below), whose sum is σ = 170745652548. Its totient is φ = 143317435392.

The previous prime is 156504640657. The next prime is 156504640673. The reversal of 156504640661 is 166046405651.

It can be written as a sum of positive squares in 6 ways, for example, as 9424720561 + 147079920100 = 97081^2 + 383510^2 .

It is not a de Polignac number, because 156504640661 - 2² = 156504640657 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (156504640601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7307396 + ... + 7328781.

It is an arithmetic number, because the mean of its divisors is an integer number (14228804379).

Almost surely, 2^156504640661 is an apocalyptic number.

It is an amenable number.

156504640661 is a deficient number, since it is larger than the sum of its proper divisors (14241011887).

156504640661 is a wasteful number, since it uses less digits than its factorization.

156504640661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14636248 (or 14636231 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 44.

The spelling of 156504640661 in words is "one hundred fifty-six billion, five hundred four million, six hundred forty thousand, six hundred sixty-one".