78398280 has 80 divisors (see below), whose sum is σ = 263516220. Its totient is φ = 20905344.

The previous prime is 78398267. The next prime is 78398297. The reversal of 78398280 is 8289387.

It can be written as a sum of positive squares in 2 ways, for example, as 74960964 + 3437316 = 8658^2 + 1854^2 .

It is a super-2 number, since 2×78398280² = 12292580613916800, which contains 22 as substring.

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

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 8859 + ... + 15338.

Almost surely, 2^78398280 is an apocalyptic number.

It is an amenable number.

78398280 is an abundant number, since it is smaller than the sum of its proper divisors (185117940).

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

78398280 is a wasteful number, since it uses less digits than its factorization.

78398280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24220 (or 24207 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 45.

The square root of 78398280 is about 8854.2803208392. The cubic root of 78398280 is about 427.9918623078.

The spelling of 78398280 in words is "seventy-eight million, three hundred ninety-eight thousand, two hundred eighty".