79840131840 has 720 divisors, whose sum is σ = 340761028608. Its totient is φ = 17452081152.

The previous prime is 79840131821. The next prime is 79840131841. The reversal of 79840131840 is 4813104897.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (720).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (79840131841) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 16690089 + ... + 16694871.

Almost surely, 2^79840131840 is an apocalyptic number.

79840131840 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 79840131840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (170380514304).

79840131840 is an abundant number, since it is smaller than the sum of its proper divisors (260920896768).

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

79840131840 is a wasteful number, since it uses less digits than its factorization.

79840131840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4846 (or 4823 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 45.

The spelling of 79840131840 in words is "seventy-nine billion, eight hundred forty million, one hundred thirty-one thousand, eight hundred forty".