77989731 has 8 divisors (see below), whose sum is σ = 104031504. Its totient is φ = 51970560.

The previous prime is 77989687. The next prime is 77989733. The reversal of 77989731 is 13798977.

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 77989731 - 2¹⁷ = 77858659 is a prime.

It is a super-2 number, since 2×77989731² = 12164796282904722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (77989733) 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, 5611 + ... + 13691.

It is an arithmetic number, because the mean of its divisors is an integer number (13003938).

Almost surely, 2^77989731 is an apocalyptic number.

77989731 is a deficient number, since it is larger than the sum of its proper divisors (26041773).

77989731 is a wasteful number, since it uses less digits than its factorization.

77989731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11301.

The product of its digits is 666792, while the sum is 51.

The square root of 77989731 is about 8831.1794795486. The cubic root of 77989731 is about 427.2471169486.

The spelling of 77989731 in words is "seventy-seven million, nine hundred eighty-nine thousand, seven hundred thirty-one".