77155985961193 has 2 divisors, whose sum is σ = 77155985961194. Its totient is φ = 77155985961192.

The previous prime is 77155985961191. The next prime is 77155985961281. The reversal of 77155985961193 is 39116958955177.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 39696653078784 + 37459332882409 = 6300528^2 + 6120403^2 .

It is a cyclic number.

It is not a de Polignac number, because 77155985961193 - 2¹ = 77155985961191 is a prime.

It is a super-2 number, since 2×77155985961193² (a number of 29 digits) contains 22 as substring.

Together with 77155985961191, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (77155985961191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38577992980596 + 38577992980597.

It is an arithmetic number, because the mean of its divisors is an integer number (38577992980597).

Almost surely, 2^{77155985961193} is an apocalyptic number.

It is an amenable number.

77155985961193 is a deficient number, since it is larger than the sum of its proper divisors (1).

77155985961193 is an equidigital number, since it uses as much as digits as its factorization.

77155985961193 is an evil number, because the sum of its binary digits is even.

The product of its digits is 642978000, while the sum is 76.

The spelling of 77155985961193 in words is "seventy-seven trillion, one hundred fifty-five billion, nine hundred eighty-five million, nine hundred sixty-one thousand, one hundred ninety-three".