61777477631 has 2 divisors, whose sum is σ = 61777477632. Its totient is φ = 61777477630.

The previous prime is 61777477571. The next prime is 61777477717. The reversal of 61777477631 is 13677477716.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61777477631 is a prime.

It is a super-2 number, since 2×61777477631² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61777477031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30888738815 + 30888738816.

It is an arithmetic number, because the mean of its divisors is an integer number (30888738816).

Almost surely, 2^61777477631 is an apocalyptic number.

61777477631 is a deficient number, since it is larger than the sum of its proper divisors (1).

61777477631 is an equidigital number, since it uses as much as digits as its factorization.

61777477631 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7260624, while the sum is 56.

The spelling of 61777477631 in words is "sixty-one billion, seven hundred seventy-seven million, four hundred seventy-seven thousand, six hundred thirty-one".