77931643 has 8 divisors (see below), whose sum is σ = 79021712. Its totient is φ = 76847616.

The previous prime is 77931617. The next prime is 77931647. The reversal of 77931643 is 34613977.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 77931643 - 2⁹ = 77931131 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 77931596 and 77931605.

It is not an unprimeable number, because it can be changed into a prime (77931647) 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 7 ways as a sum of consecutive naturals, for example, 28471 + ... + 31087.

It is an arithmetic number, because the mean of its divisors is an integer number (9877714).

Almost surely, 2^77931643 is an apocalyptic number.

77931643 is a deficient number, since it is larger than the sum of its proper divisors (1090069).

77931643 is a wasteful number, since it uses less digits than its factorization.

77931643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3021.

The product of its digits is 95256, while the sum is 40.

The square root of 77931643 is about 8827.8900650155. The cubic root of 77931643 is about 427.1410171054.

The spelling of 77931643 in words is "seventy-seven million, nine hundred thirty-one thousand, six hundred forty-three".