7881394 has 4 divisors (see below), whose sum is σ = 11822094. Its totient is φ = 3940696.

The previous prime is 7881373. The next prime is 7881487. The reversal of 7881394 is 4931887.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 6225025 + 1656369 = 2495^2 + 1287^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1970347 + ... + 1970350.

Almost surely, 2^7881394 is an apocalyptic number.

7881394 is a deficient number, since it is larger than the sum of its proper divisors (3940700).

7881394 is a wasteful number, since it uses less digits than its factorization.

7881394 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3940699.

The product of its digits is 48384, while the sum is 40.

The square root of 7881394 is about 2807.3820545127. The cubic root of 7881394 is about 199.0066915252.

The spelling of 7881394 in words is "seven million, eight hundred eighty-one thousand, three hundred ninety-four".