78524820 has 72 divisors (see below), whose sum is σ = 259852320. Its totient is φ = 19035840.

The previous prime is 78524807. The next prime is 78524821. The reversal of 78524820 is 2842587.

It is a happy number.

It is a super-2 number, since 2×78524820² = 12332294712064800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78524821) 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, 17850 + ... + 21809.

It is an arithmetic number, because the mean of its divisors is an integer number (3609060).

Almost surely, 2^78524820 is an apocalyptic number.

It is an amenable number.

78524820 is an abundant number, since it is smaller than the sum of its proper divisors (181327500).

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

78524820 is a wasteful number, since it uses less digits than its factorization.

78524820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39685 (or 39680 counting only the distinct ones).

The product of its (nonzero) digits is 35840, while the sum is 36.

The square root of 78524820 is about 8861.4231362688. The cubic root of 78524820 is about 428.2220075700. Note that the first 3 decimals are identical.

The spelling of 78524820 in words is "seventy-eight million, five hundred twenty-four thousand, eight hundred twenty".