840040668 has 36 divisors (see below), whose sum is σ = 2130248848. Its totient is φ = 279115200.

The previous prime is 840040639. The next prime is 840040679. The reversal of 840040668 is 866040048.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 26008 + ... + 48543.

Almost surely, 2^840040668 is an apocalyptic number.

It is an amenable number.

840040668 is an abundant number, since it is smaller than the sum of its proper divisors (1290208180).

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

840040668 is a wasteful number, since it uses less digits than its factorization.

840040668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74874 (or 74869 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 36.

The square root of 840040668 is about 28983.4550735415. The cubic root of 840040668 is about 943.5540227365.

The spelling of 840040668 in words is "eight hundred forty million, forty thousand, six hundred sixty-eight".