78120064 has 64 divisors (see below), whose sum is σ = 171629280. Its totient is φ = 35123200.

The previous prime is 78120059. The next prime is 78120073. The reversal of 78120064 is 46002187.

It is a tau number, because it is divible by the number of its divisors (64).

It is a super-2 number, since 2×78120064² = 12205488798728192, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 158859 + ... + 159349.

Almost surely, 2^78120064 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 78120064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (85814640).

78120064 is an abundant number, since it is smaller than the sum of its proper divisors (93509216).

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

78120064 is a wasteful number, since it uses less digits than its factorization.

78120064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 629 (or 617 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 28.

The square root of 78120064 is about 8838.5555380956. Note that the first 4 decimals coincide. The cubic root of 78120064 is about 427.4849833422.

The spelling of 78120064 in words is "seventy-eight million, one hundred twenty thousand, sixty-four".