78172722 has 64 divisors (see below), whose sum is σ = 183202560. Its totient is φ = 24659712.

The previous prime is 78172711. The next prime is 78172733. The reversal of 78172722 is 22727187.

It is an interprime number because it is at equal distance from previous prime (78172711) and next prime (78172733).

It is a super-2 number, since 2×78172722² = 12221948929778568, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 140068 + ... + 140624.

It is an arithmetic number, because the mean of its divisors is an integer number (2862540).

Almost surely, 2^78172722 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78172722, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (91601280).

78172722 is an abundant number, since it is smaller than the sum of its proper divisors (105029838).

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

78172722 is a wasteful number, since it uses less digits than its factorization.

78172722 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 704 (or 698 counting only the distinct ones).

The product of its digits is 21952, while the sum is 36.

The square root of 78172722 is about 8841.5339166912. The cubic root of 78172722 is about 427.5810126555.

The spelling of 78172722 in words is "seventy-eight million, one hundred seventy-two thousand, seven hundred twenty-two".