77986731 has 32 divisors (see below), whose sum is σ = 111421440. Its totient is φ = 48441600.

The previous prime is 77986729. The next prime is 77986747. The reversal of 77986731 is 13768977.

It is a happy number.

It is not a de Polignac number, because 77986731 - 2¹ = 77986729 is a prime.

It is a super-2 number, since 2×77986731² = 12163860424132722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (77986751) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 334591 + ... + 334823.

It is an arithmetic number, because the mean of its divisors is an integer number (3481920).

Almost surely, 2^77986731 is an apocalyptic number.

77986731 is a deficient number, since it is larger than the sum of its proper divisors (33434709).

77986731 is a wasteful number, since it uses less digits than its factorization.

77986731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 387.

The product of its digits is 444528, while the sum is 48.

The square root of 77986731 is about 8831.0096251788. The cubic root of 77986731 is about 427.2416386300.

The spelling of 77986731 in words is "seventy-seven million, nine hundred eighty-six thousand, seven hundred thirty-one".