78775920 has 240 divisors, whose sum is σ = 284124672. Its totient is φ = 19514880.

The previous prime is 78775913. The next prime is 78775937. The reversal of 78775920 is 2957787.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1109485 + ... + 1109555.

Almost surely, 2^78775920 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 78775920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (142062336).

78775920 is an abundant number, since it is smaller than the sum of its proper divisors (205348752).

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

78775920 is a wasteful number, since it uses less digits than its factorization.

78775920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180 (or 171 counting only the distinct ones).

The product of its (nonzero) digits is 246960, while the sum is 45.

The square root of 78775920 is about 8875.5799810491. The cubic root of 78775920 is about 428.6779658950.

The spelling of 78775920 in words is "seventy-eight million, seven hundred seventy-five thousand, nine hundred twenty".