77747566353681 has 32 divisors (see below), whose sum is σ = 119184603310080. Its totient is φ = 44160147386496.

The previous prime is 77747566353659. The next prime is 77747566353697. The reversal of 77747566353681 is 18635366574777.

It is not a de Polignac number, because 77747566353681 - 2²⁵ = 77747532799249 is a prime.

It is a super-2 number, since 2×77747566353681² (a number of 29 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (77747566353641) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 170868805 + ... + 171323213.

It is an arithmetic number, because the mean of its divisors is an integer number (3724518853440).

Almost surely, 2^{77747566353681} is an apocalyptic number.

It is an amenable number.

77747566353681 is a deficient number, since it is larger than the sum of its proper divisors (41437036956399).

77747566353681 is a wasteful number, since it uses less digits than its factorization.

77747566353681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 503373.

The product of its digits is 3734035200, while the sum is 75.

The spelling of 77747566353681 in words is "seventy-seven trillion, seven hundred forty-seven billion, five hundred sixty-six million, three hundred fifty-three thousand, six hundred eighty-one".