79581390 has 96 divisors (see below), whose sum is σ = 227525760. Its totient is φ = 17752896.

The previous prime is 79581377. The next prime is 79581391. The reversal of 79581390 is 9318597.

It is a happy number.

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 (79581391) 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, 62581 + ... + 63839.

It is an arithmetic number, because the mean of its divisors is an integer number (2370060).

Almost surely, 2^79581390 is an apocalyptic number.

79581390 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 79581390, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (113762880).

79581390 is an abundant number, since it is smaller than the sum of its proper divisors (147944370).

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

79581390 is a wasteful number, since it uses less digits than its factorization.

79581390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1326 (or 1319 counting only the distinct ones).

The product of its (nonzero) digits is 68040, while the sum is 42.

The square root of 79581390 is about 8920.8402070657. The cubic root of 79581390 is about 430.1340667231.

The spelling of 79581390 in words is "seventy-nine million, five hundred eighty-one thousand, three hundred ninety".