78644427 has 16 divisors (see below), whose sum is σ = 108598272. Its totient is φ = 50571360.

The previous prime is 78644417. The next prime is 78644443. The reversal of 78644427 is 72444687.

It is not a de Polignac number, because 78644427 - 2¹⁹ = 78120139 is a prime.

It is not an unprimeable number, because it can be changed into a prime (78644417) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31053 + ... + 33489.

It is an arithmetic number, because the mean of its divisors is an integer number (6787392).

Almost surely, 2^78644427 is an apocalyptic number.

78644427 is a deficient number, since it is larger than the sum of its proper divisors (29953845).

78644427 is a wasteful number, since it uses less digits than its factorization.

78644427 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2818.

The product of its digits is 301056, while the sum is 42.

The square root of 78644427 is about 8868.1693150278. The cubic root of 78644427 is about 428.4393162155.

The spelling of 78644427 in words is "seventy-eight million, six hundred forty-four thousand, four hundred twenty-seven".