78918840 has 512 divisors, whose sum is σ = 358041600. Its totient is φ = 14929920.

The previous prime is 78918787. The next prime is 78918841. The reversal of 78918840 is 4881987.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78918841) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 1081044 + ... + 1081116.

It is an arithmetic number, because the mean of its divisors is an integer number (699300).

Almost surely, 2^78918840 is an apocalyptic number.

78918840 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78918840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (179020800).

78918840 is an abundant number, since it is smaller than the sum of its proper divisors (279122760).

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

78918840 is a wasteful number, since it uses less digits than its factorization.

78918840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 124 (or 114 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 45.

The square root of 78918840 is about 8883.6276374013. The cubic root of 78918840 is about 428.9370537015.

The spelling of 78918840 in words is "seventy-eight million, nine hundred eighteen thousand, eight hundred forty".