394487843658978 has 16 divisors (see below), whose sum is σ = 807323959116576. Its totient is φ = 128437902586560.

The previous prime is 394487843658943. The next prime is 394487843658983. The reversal of 394487843658978 is 879856348784493.

It is a junction number, because it is equal to n+sod(n) for n = 394487843658891 and 394487843658900.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 764511324663 + ... + 764511325178.

It is an arithmetic number, because the mean of its divisors is an integer number (50457747444786).

Almost surely, 2^{394487843658978} is an apocalyptic number.

394487843658978 is an abundant number, since it is smaller than the sum of its proper divisors (412836115457598).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

394487843658978 is a wasteful number, since it uses less digits than its factorization.

394487843658978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1529022649889.

The product of its digits is 280921374720, while the sum is 93.

The spelling of 394487843658978 in words is "three hundred ninety-four trillion, four hundred eighty-seven billion, eight hundred forty-three million, six hundred fifty-eight thousand, nine hundred seventy-eight".