78501994 has 4 divisors (see below), whose sum is σ = 117752994. Its totient is φ = 39250996.

The previous prime is 78501989. The next prime is 78502033. The reversal of 78501994 is 49910587.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 49910587 = 19 ⋅2626873.

It can be written as a sum of positive squares in only one way, i.e., 61387225 + 17114769 = 7835^2 + 4137^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 78501994.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19625497 + ... + 19625500.

Almost surely, 2^78501994 is an apocalyptic number.

78501994 is a deficient number, since it is larger than the sum of its proper divisors (39251000).

78501994 is a wasteful number, since it uses less digits than its factorization.

78501994 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39250999.

The product of its (nonzero) digits is 90720, while the sum is 43.

The square root of 78501994 is about 8860.1351005501. The cubic root of 78501994 is about 428.1805109544.

The spelling of 78501994 in words is "seventy-eight million, five hundred one thousand, nine hundred ninety-four".