840105945 has 32 divisors (see below), whose sum is σ = 1706883840. Its totient is φ = 384048000.

The previous prime is 840105941. The next prime is 840105947. The reversal of 840105945 is 549501048.

It is not a de Polignac number, because 840105945 - 2² = 840105941 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (840105941) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 443556 + ... + 445445.

It is an arithmetic number, because the mean of its divisors is an integer number (53340120).

Almost surely, 2^840105945 is an apocalyptic number.

It is an amenable number.

840105945 is an abundant number, since it is smaller than the sum of its proper divisors (866777895).

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

840105945 is a wasteful number, since it uses less digits than its factorization.

840105945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 889022 (or 889016 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 36.

The square root of 840105945 is about 28984.5811596442. The cubic root of 840105945 is about 943.5784623393.

The spelling of 840105945 in words is "eight hundred forty million, one hundred five thousand, nine hundred forty-five".