78538780 has 72 divisors (see below), whose sum is σ = 180386640. Its totient is φ = 28627200.

The previous prime is 78538777. The next prime is 78538783. The reversal of 78538780 is 8783587.

It is an interprime number because it is at equal distance from previous prime (78538777) and next prime (78538783).

It is a self number, because there is not a number n which added to its sum of digits gives 78538780.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78538783) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1106145 + ... + 1106215.

It is an arithmetic number, because the mean of its divisors is an integer number (2505370).

Almost surely, 2^78538780 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 78538780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (90193320).

78538780 is an abundant number, since it is smaller than the sum of its proper divisors (101847860).

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

78538780 is a wasteful number, since it uses less digits than its factorization.

78538780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 211 (or 138 counting only the distinct ones).

The product of its (nonzero) digits is 376320, while the sum is 46.

The square root of 78538780 is about 8862.2107851258. The cubic root of 78538780 is about 428.2473822435.

The spelling of 78538780 in words is "seventy-eight million, five hundred thirty-eight thousand, seven hundred eighty".