78122720 has 144 divisors (see below), whose sum is σ = 210706272. Its totient is φ = 27202560.

The previous prime is 78122717. The next prime is 78122741. The reversal of 78122720 is 2722187.

It is a super-2 number, since 2×78122720² = 12206318760396800, 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 23 ways as a sum of consecutive naturals, for example, 1100285 + ... + 1100355.

It is an arithmetic number, because the mean of its divisors is an integer number (1463238).

Almost surely, 2^78122720 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 78122720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (105353136).

78122720 is an abundant number, since it is smaller than the sum of its proper divisors (132583552).

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

78122720 is a wasteful number, since it uses less digits than its factorization.

78122720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145 (or 114 counting only the distinct ones).

The product of its (nonzero) digits is 3136, while the sum is 29.

The square root of 78122720 is about 8838.7057876139. The cubic root of 78122720 is about 427.4898279672.

The spelling of 78122720 in words is "seventy-eight million, one hundred twenty-two thousand, seven hundred twenty".