394951981678 has 4 divisors (see below), whose sum is σ = 592427972520. Its totient is φ = 197475990838.

The previous prime is 394951981661. The next prime is 394951981727. The reversal of 394951981678 is 876189159493.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 98737995418 + ... + 98737995421.

It is an arithmetic number, because the mean of its divisors is an integer number (148106993130).

Almost surely, 2^394951981678 is an apocalyptic number.

394951981678 is a deficient number, since it is larger than the sum of its proper divisors (197475990842).

394951981678 is a wasteful number, since it uses less digits than its factorization.

394951981678 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 197475990841.

The product of its digits is 117573120, while the sum is 70.

The spelling of 394951981678 in words is "three hundred ninety-four billion, nine hundred fifty-one million, nine hundred eighty-one thousand, six hundred seventy-eight".