78781215 has 8 divisors (see below), whose sum is σ = 126049968. Its totient is φ = 42016640.

The previous prime is 78781207. The next prime is 78781231. The reversal of 78781215 is 51218787.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 78781215 - 2³ = 78781207 is a prime.

It is a congruent number.

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, 2626026 + ... + 2626055.

It is an arithmetic number, because the mean of its divisors is an integer number (15756246).

Almost surely, 2^78781215 is an apocalyptic number.

78781215 is a deficient number, since it is larger than the sum of its proper divisors (47268753).

78781215 is a wasteful number, since it uses less digits than its factorization.

78781215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5252089.

The product of its digits is 31360, while the sum is 39.

The square root of 78781215 is about 8875.8782664027. The cubic root of 78781215 is about 428.6875703484.

The spelling of 78781215 in words is "seventy-eight million, seven hundred eighty-one thousand, two hundred fifteen".