78865542 has 128 divisors (see below), whose sum is σ = 215040000. Its totient is φ = 20925216.

The previous prime is 78865531. The next prime is 78865573. The reversal of 78865542 is 24556887.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 567309 + ... + 567447.

It is an arithmetic number, because the mean of its divisors is an integer number (1680000).

Almost surely, 2^78865542 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78865542, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (107520000).

78865542 is an abundant number, since it is smaller than the sum of its proper divisors (136174458).

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

78865542 is a wasteful number, since it uses less digits than its factorization.

78865542 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 255 (or 249 counting only the distinct ones).

The product of its digits is 537600, while the sum is 45.

The square root of 78865542 is about 8880.6273427050. The cubic root of 78865542 is about 428.8404707836.

The spelling of 78865542 in words is "seventy-eight million, eight hundred sixty-five thousand, five hundred forty-two".