840661911 has 12 divisors (see below), whose sum is σ = 1242529288. Its totient is φ = 547407504.

The previous prime is 840661837. The next prime is 840661919. The reversal of 840661911 is 119166048.

It is a happy number.

It is not a de Polignac number, because 840661911 - 2⁹ = 840661399 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (840661919) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1085740 + ... + 1086513.

Almost surely, 2^840661911 is an apocalyptic number.

840661911 is a deficient number, since it is larger than the sum of its proper divisors (401867377).

840661911 is a wasteful number, since it uses less digits than its factorization.

840661911 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2172302 (or 2172299 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 36.

The square root of 840661911 is about 28994.1702933538. The cubic root of 840661911 is about 943.7865638159.

The spelling of 840661911 in words is "eight hundred forty million, six hundred sixty-one thousand, nine hundred eleven".