78715215 has 36 divisors (see below), whose sum is σ = 138787272. Its totient is φ = 41270880.

The previous prime is 78715213. The next prime is 78715267. The reversal of 78715215 is 51251787.

It is not a de Polignac number, because 78715215 - 2¹ = 78715213 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 78715215.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78715211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 226672 + ... + 227018.

It is an arithmetic number, because the mean of its divisors is an integer number (3855202).

Almost surely, 2^78715215 is an apocalyptic number.

78715215 is a deficient number, since it is larger than the sum of its proper divisors (60072057).

78715215 is a wasteful number, since it uses less digits than its factorization.

78715215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 500 (or 426 counting only the distinct ones).

The product of its digits is 19600, while the sum is 36.

The square root of 78715215 is about 8872.1595454545. The cubic root of 78715215 is about 428.5678240173.

The spelling of 78715215 in words is "seventy-eight million, seven hundred fifteen thousand, two hundred fifteen".