76639920 has 240 divisors, whose sum is σ = 291767040. Its totient is φ = 16595712.

The previous prime is 76639909. The next prime is 76639921. The reversal of 76639920 is 2993667.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (76639921) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4033671 + ... + 4033689.

It is an arithmetic number, because the mean of its divisors is an integer number (1215696).

Almost surely, 2^76639920 is an apocalyptic number.

76639920 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 76639920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (145883520).

76639920 is an abundant number, since it is smaller than the sum of its proper divisors (215127120).

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

76639920 is an equidigital number, since it uses as much as digits as its factorization.

76639920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70 (or 36 counting only the distinct ones).

The product of its (nonzero) digits is 122472, while the sum is 42.

The square root of 76639920 is about 8754.4228821779. The cubic root of 76639920 is about 424.7678917146.

The spelling of 76639920 in words is "seventy-six million, six hundred thirty-nine thousand, nine hundred twenty".