61312508977 has 2 divisors, whose sum is σ = 61312508978. Its totient is φ = 61312508976.

The previous prime is 61312508909. The next prime is 61312509007. The reversal of 61312508977 is 77980521316.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 51506756401 + 9805752576 = 226951^2 + 99024^2 .

It is a cyclic number.

It is not a de Polignac number, because 61312508977 - 2¹⁹ = 61311984689 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 61312508977.

It is not a weakly prime, because it can be changed into another prime (61312508177) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30656254488 + 30656254489.

It is an arithmetic number, because the mean of its divisors is an integer number (30656254489).

Almost surely, 2^61312508977 is an apocalyptic number.

It is an amenable number.

61312508977 is a deficient number, since it is larger than the sum of its proper divisors (1).

61312508977 is an equidigital number, since it uses as much as digits as its factorization.

61312508977 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 635040, while the sum is 49.

The spelling of 61312508977 in words is "sixty-one billion, three hundred twelve million, five hundred eight thousand, nine hundred seventy-seven".