77677581981 has 16 divisors (see below), whose sum is σ = 106919516160. Its totient is φ = 50110614960.

The previous prime is 77677581977. The next prime is 77677581997. The reversal of 77677581981 is 18918577677.

It is not a de Polignac number, because 77677581981 - 2² = 77677581977 is a prime.

It is a super-2 number, since 2×77677581981² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77677581901) 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, 1568050 + ... + 1616828.

It is an arithmetic number, because the mean of its divisors is an integer number (6682469760).

Almost surely, 2^77677581981 is an apocalyptic number.

It is an amenable number.

77677581981 is a deficient number, since it is larger than the sum of its proper divisors (29241934179).

77677581981 is a wasteful number, since it uses less digits than its factorization.

77677581981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65936.

The product of its digits is 41489280, while the sum is 66.

The spelling of 77677581981 in words is "seventy-seven billion, six hundred seventy-seven million, five hundred eighty-one thousand, nine hundred eighty-one".