78257218 has 16 divisors (see below), whose sum is σ = 126616896. Its totient is φ = 36061200.

The previous prime is 78257213. The next prime is 78257261. The reversal of 78257218 is 81275287.

It is a super-2 number, since 2×78257218² = 12248384338199048, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (78257213) 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, 17293 + ... + 21343.

It is an arithmetic number, because the mean of its divisors is an integer number (7913556).

Almost surely, 2^78257218 is an apocalyptic number.

78257218 is a deficient number, since it is larger than the sum of its proper divisors (48359678).

78257218 is a wasteful number, since it uses less digits than its factorization.

78257218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4809.

The product of its digits is 62720, while the sum is 40.

The square root of 78257218 is about 8846.3109825509. The cubic root of 78257218 is about 427.7350129898.

The spelling of 78257218 in words is "seventy-eight million, two hundred fifty-seven thousand, two hundred eighteen".