840393992 has 16 divisors (see below), whose sum is σ = 1582280700. Its totient is φ = 418452480.

The previous prime is 840393979. The next prime is 840394019. The reversal of 840393992 is 299393048.

It can be written as a sum of positive squares in 2 ways, for example, as 647906116 + 192487876 = 25454^2 + 13874^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 216017 + ... + 219872.

Almost surely, 2^840393992 is an apocalyptic number.

It is an amenable number.

840393992 is a deficient number, since it is larger than the sum of its proper divisors (741886708).

840393992 is a wasteful number, since it uses less digits than its factorization.

840393992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 436136 (or 436132 counting only the distinct ones).

The product of its (nonzero) digits is 419904, while the sum is 47.

The square root of 840393992 is about 28989.5497032983. The cubic root of 840393992 is about 943.6862915519.

The spelling of 840393992 in words is "eight hundred forty million, three hundred ninety-three thousand, nine hundred ninety-two".