78139344 has 80 divisors (see below), whose sum is σ = 220700160. Its totient is φ = 23715840.

The previous prime is 78139339. The next prime is 78139351. The reversal of 78139344 is 44393187.

It is a super-2 number, since 2×78139344² = 12211514161500672, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23752 + ... + 26840.

It is an arithmetic number, because the mean of its divisors is an integer number (2758752).

Almost surely, 2^78139344 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78139344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (110350080).

78139344 is an abundant number, since it is smaller than the sum of its proper divisors (142560816).

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

78139344 is a wasteful number, since it uses less digits than its factorization.

78139344 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3148 (or 3142 counting only the distinct ones).

The product of its digits is 72576, while the sum is 39.

The square root of 78139344 is about 8839.6461467640. The cubic root of 78139344 is about 427.5201481561.

The spelling of 78139344 in words is "seventy-eight million, one hundred thirty-nine thousand, three hundred forty-four".