12931358777 has 4 divisors (see below), whose sum is σ = 12931590900. Its totient is φ = 12931126656.

The previous prime is 12931358731. The next prime is 12931358809. The reversal of 12931358777 is 77785313921.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 77785313921 = 7 ⋅11112187703.

It can be written as a sum of positive squares in 2 ways, for example, as 9647954176 + 3283404601 = 98224^2 + 57301^2 .

It is a cyclic number.

It is not a de Polignac number, because 12931358777 - 2⁸ = 12931358521 is a prime.

It is a deceptive number, since it divides R_12931358776.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12931355777) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23213 + ... + 162485.

It is an arithmetic number, because the mean of its divisors is an integer number (3232897725).

Almost surely, 2^12931358777 is an apocalyptic number.

12931358777 is the 92849-th pentagonal number.

It is an amenable number.

12931358777 is a deficient number, since it is larger than the sum of its proper divisors (232123).

12931358777 is an equidigital number, since it uses as much as digits as its factorization.

12931358777 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 232122.

The product of its digits is 2222640, while the sum is 53.

The spelling of 12931358777 in words is "twelve billion, nine hundred thirty-one million, three hundred fifty-eight thousand, seven hundred seventy-seven".