77136840 has 256 divisors, whose sum is σ = 288921600. Its totient is φ = 18144000.

The previous prime is 77136833. The next prime is 77136841. The reversal of 77136840 is 4863177.

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

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

It is a junction number, because it is equal to n+sod(n) for n = 77136795 and 77136804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77136841) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 510765 + ... + 510915.

It is an arithmetic number, because the mean of its divisors is an integer number (1128600).

Almost surely, 2^77136840 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 77136840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (144460800).

77136840 is an abundant number, since it is smaller than the sum of its proper divisors (211784760).

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

77136840 is a wasteful number, since it uses less digits than its factorization.

77136840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 225 (or 215 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 36.

The square root of 77136840 is about 8782.7581089314. The cubic root of 77136840 is about 425.6839552327.

The spelling of 77136840 in words is "seventy-seven million, one hundred thirty-six thousand, eight hundred forty".