77831136 has 72 divisors (see below), whose sum is σ = 225552600. Its totient is φ = 25449216.

The previous prime is 77831129. The next prime is 77831137. The reversal of 77831136 is 63113877.

It is a tau number, because it is divible by the number of its divisors (72).

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 77831136.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77831137) 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 11 ways as a sum of consecutive naturals, for example, 12715 + ... + 17813.

It is an arithmetic number, because the mean of its divisors is an integer number (3132675).

Almost surely, 2^77831136 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77831136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (112776300).

77831136 is an abundant number, since it is smaller than the sum of its proper divisors (147721464).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

77831136 is a wasteful number, since it uses less digits than its factorization.

77831136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5168 (or 5157 counting only the distinct ones).

The product of its digits is 21168, while the sum is 36.

The square root of 77831136 is about 8822.1956450761. The cubic root of 77831136 is about 426.9573128170.

It can be divided in two parts, 7783 and 1136, that multiplied together give a palindrome (8841488).

The spelling of 77831136 in words is "seventy-seven million, eight hundred thirty-one thousand, one hundred thirty-six".