78921580 has 24 divisors (see below), whose sum is σ = 166016592. Its totient is φ = 31515072.

The previous prime is 78921539. The next prime is 78921581. The reversal of 78921580 is 8512987.

It is not an unprimeable number, because it can be changed into a prime (78921581) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10039 + ... + 16081.

It is an arithmetic number, because the mean of its divisors is an integer number (6917358).

Almost surely, 2^78921580 is an apocalyptic number.

It is an amenable number.

78921580 is an abundant number, since it is smaller than the sum of its proper divisors (87095012).

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

78921580 is a wasteful number, since it uses less digits than its factorization.

78921580 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6705 (or 6703 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 40.

The square root of 78921580 is about 8883.7818523419. The cubic root of 78921580 is about 428.9420177630.

The spelling of 78921580 in words is "seventy-eight million, nine hundred twenty-one thousand, five hundred eighty".