393993998 has 16 divisors (see below), whose sum is σ = 602334960. Its totient is φ = 193233600.

The previous prime is 393993991. The next prime is 393994021. The reversal of 393993998 is 899399393.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 393993998.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (393993991) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 41978 + ... + 50498.

It is an arithmetic number, because the mean of its divisors is an integer number (37645935).

Almost surely, 2^393993998 is an apocalyptic number.

393993998 is a deficient number, since it is larger than the sum of its proper divisors (208340962).

393993998 is a wasteful number, since it uses less digits than its factorization.

393993998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8963.

The product of its digits is 12754584, while the sum is 62.

The square root of 393993998 is about 19849.2820525076. The cubic root of 393993998 is about 733.0999704206.

The spelling of 393993998 in words is "three hundred ninety-three million, nine hundred ninety-three thousand, nine hundred ninety-eight".