78005820 has 24 divisors (see below), whose sum is σ = 218416464. Its totient is φ = 20801536.

The previous prime is 78005819. The next prime is 78005831. The reversal of 78005820 is 2850087.

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 649989 + ... + 650108.

It is an arithmetic number, because the mean of its divisors is an integer number (9100686).

Almost surely, 2^78005820 is an apocalyptic number.

It is an amenable number.

78005820 is an abundant number, since it is smaller than the sum of its proper divisors (140410644).

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

78005820 is a wasteful number, since it uses less digits than its factorization.

78005820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1300109 (or 1300107 counting only the distinct ones).

The product of its (nonzero) digits is 4480, while the sum is 30.

The square root of 78005820 is about 8832.0903527987. The cubic root of 78005820 is about 427.2764947745.

The spelling of 78005820 in words is "seventy-eight million, five thousand, eight hundred twenty".