78909072 has 80 divisors (see below), whose sum is σ = 223795200. Its totient is φ = 23760000.

The previous prime is 78909041. The next prime is 78909079. The reversal of 78909072 is 27090987.

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (78909079) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 104697 + ... + 105447.

It is an arithmetic number, because the mean of its divisors is an integer number (2797440).

Almost surely, 2^78909072 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 78909072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (111897600).

78909072 is an abundant number, since it is smaller than the sum of its proper divisors (144886128).

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

78909072 is a wasteful number, since it uses less digits than its factorization.

78909072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 972 (or 966 counting only the distinct ones).

The product of its (nonzero) digits is 63504, while the sum is 42.

The square root of 78909072 is about 8883.0778449814. The cubic root of 78909072 is about 428.9193560685.

The spelling of 78909072 in words is "seventy-eight million, nine hundred nine thousand, seventy-two".