79815680 has 176 divisors, whose sum is σ = 233456256. Its totient is φ = 25559040.

The previous prime is 79815679. The next prime is 79815683. The reversal of 79815680 is 8651897.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79815683) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 609215 + ... + 609345.

It is an arithmetic number, because the mean of its divisors is an integer number (1326456).

Almost surely, 2^79815680 is an apocalyptic number.

79815680 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 79815680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (116728128).

79815680 is an abundant number, since it is smaller than the sum of its proper divisors (153640576).

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

79815680 is a wasteful number, since it uses less digits than its factorization.

79815680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180 (or 162 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 44.

The square root of 79815680 is about 8933.9621669224. The cubic root of 79815680 is about 430.5557623647. Note that the first 3 decimals are identical.

The spelling of 79815680 in words is "seventy-nine million, eight hundred fifteen thousand, six hundred eighty".