78409660 has 48 divisors (see below), whose sum is σ = 193281984. Its totient is φ = 26155008.

The previous prime is 78409651. The next prime is 78409663. The reversal of 78409660 is 6690487.

It is a super-2 number, since 2×78409660² = 12296149562631200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78409663) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2389 + ... + 12748.

It is an arithmetic number, because the mean of its divisors is an integer number (4026708).

Almost surely, 2^78409660 is an apocalyptic number.

78409660 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

78409660 is an abundant number, since it is smaller than the sum of its proper divisors (114872324).

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

78409660 is a wasteful number, since it uses less digits than its factorization.

78409660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15190 (or 15188 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 40.

The square root of 78409660 is about 8854.9229245657. The cubic root of 78409660 is about 428.0125698699.

The spelling of 78409660 in words is "seventy-eight million, four hundred nine thousand, six hundred sixty".