261637116166 has 32 divisors (see below), whose sum is σ = 418395875040. Its totient is φ = 122278657536.

The previous prime is 261637116161. The next prime is 261637116173. The reversal of 261637116166 is 661611736162.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261637116161) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7903000 + ... + 7936036.

It is an arithmetic number, because the mean of its divisors is an integer number (13074871095).

Almost surely, 2^261637116166 is an apocalyptic number.

261637116166 is a deficient number, since it is larger than the sum of its proper divisors (156758758874).

261637116166 is a wasteful number, since it uses less digits than its factorization.

261637116166 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34648.

The product of its digits is 326592, while the sum is 46.

The spelling of 261637116166 in words is "two hundred sixty-one billion, six hundred thirty-seven million, one hundred sixteen thousand, one hundred sixty-six".