77980731 has 8 divisors (see below), whose sum is σ = 109446720. Its totient is φ = 49250952.

The previous prime is 77980723. The next prime is 77980733. The reversal of 77980731 is 13708977.

It is a happy number.

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

It is not a de Polignac number, because 77980731 - 2³ = 77980723 is a prime.

It is a super-2 number, since 2×77980731² = 12161988814588722, which contains 22 as substring.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (77980733) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 683985 + ... + 684098.

It is an arithmetic number, because the mean of its divisors is an integer number (13680840).

Almost surely, 2^77980731 is an apocalyptic number.

77980731 is a deficient number, since it is larger than the sum of its proper divisors (31465989).

77980731 is a wasteful number, since it uses less digits than its factorization.

77980731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1368105.

The product of its (nonzero) digits is 74088, while the sum is 42.

The square root of 77980731 is about 8830.6699066379. The cubic root of 77980731 is about 427.2306815712.

The spelling of 77980731 in words is "seventy-seven million, nine hundred eighty thousand, seven hundred thirty-one".