78721512 has 32 divisors (see below), whose sum is σ = 197225280. Its totient is φ = 26184320.

The previous prime is 78721501. The next prime is 78721529. The reversal of 78721512 is 21512787.

It is a super-2 number, since 2×78721512² = 12394152903132288, which contains 22 as substring.

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, 8812 + ... + 15332.

It is an arithmetic number, because the mean of its divisors is an integer number (6163290).

Almost surely, 2^78721512 is an apocalyptic number.

It is an amenable number.

78721512 is an abundant number, since it is smaller than the sum of its proper divisors (118503768).

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

78721512 is a wasteful number, since it uses less digits than its factorization.

78721512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7033 (or 7029 counting only the distinct ones).

The product of its digits is 7840, while the sum is 33.

The square root of 78721512 is about 8872.5144124989. The cubic root of 78721512 is about 428.5792517937.

The spelling of 78721512 in words is "seventy-eight million, seven hundred twenty-one thousand, five hundred twelve".