77666231 has 6 divisors (see below), whose sum is σ = 79356120. Its totient is φ = 76011596.

The previous prime is 77666227. The next prime is 77666249. The reversal of 77666231 is 13266677.

It is not a de Polignac number, because 77666231 - 2² = 77666227 is a prime.

It is a super-2 number, since 2×77666231² = 12064086875490722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77666201) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 15371 + ... + 19788.

It is an arithmetic number, because the mean of its divisors is an integer number (13226020).

Almost surely, 2^77666231 is an apocalyptic number.

77666231 is a deficient number, since it is larger than the sum of its proper divisors (1689889).

77666231 is an equidigital number, since it uses as much as digits as its factorization.

77666231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35253 (or 35206 counting only the distinct ones).

The product of its digits is 63504, while the sum is 38.

The square root of 77666231 is about 8812.8446599268. The cubic root of 77666231 is about 426.6555604884.

The spelling of 77666231 in words is "seventy-seven million, six hundred sixty-six thousand, two hundred thirty-one".