840442899 has 4 divisors (see below), whose sum is σ = 1120590536. Its totient is φ = 560295264.

The previous prime is 840442877. The next prime is 840442907. The reversal of 840442899 is 998244048.

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

It is not a de Polignac number, because 840442899 - 2¹² = 840438803 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (840442849) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 140073814 + ... + 140073819.

It is an arithmetic number, because the mean of its divisors is an integer number (280147634).

Almost surely, 2^840442899 is an apocalyptic number.

840442899 is a deficient number, since it is larger than the sum of its proper divisors (280147637).

840442899 is a wasteful number, since it uses less digits than its factorization.

840442899 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 280147636.

The product of its (nonzero) digits is 663552, while the sum is 48.

The square root of 840442899 is about 28990.3932191338. The cubic root of 840442899 is about 943.7045972398.

The spelling of 840442899 in words is "eight hundred forty million, four hundred forty-two thousand, eight hundred ninety-nine".