78721580 has 24 divisors (see below), whose sum is σ = 188932128. Its totient is φ = 26990208.

The previous prime is 78721549. The next prime is 78721597. The reversal of 78721580 is 8512787.

It is a plaindrome in base 12.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 281009 + ... + 281288.

It is an arithmetic number, because the mean of its divisors is an integer number (7872172).

Almost surely, 2^78721580 is an apocalyptic number.

78721580 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

78721580 is an abundant number, since it is smaller than the sum of its proper divisors (110210548).

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

78721580 is a wasteful number, since it uses less digits than its factorization.

78721580 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 562313 (or 562311 counting only the distinct ones).

The product of its (nonzero) digits is 31360, while the sum is 38.

The square root of 78721580 is about 8872.5182445572. The cubic root of 78721580 is about 428.5793751966.

The spelling of 78721580 in words is "seventy-eight million, seven hundred twenty-one thousand, five hundred eighty".