840511881 has 12 divisors (see below), whose sum is σ = 1324443120. Its totient is φ = 509401080.

The previous prime is 840511879. The next prime is 840511907. The reversal of 840511881 is 188115048.

It is a happy number.

It is not a de Polignac number, because 840511881 - 2¹ = 840511879 is a prime.

It is a super-2 number, since 2×840511881² = 1412920444204316322, which contains 22 as substring.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (840511801) 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, 4244911 + ... + 4245108.

It is an arithmetic number, because the mean of its divisors is an integer number (110370260).

Almost surely, 2^840511881 is an apocalyptic number.

It is an amenable number.

840511881 is a deficient number, since it is larger than the sum of its proper divisors (483931239).

840511881 is a wasteful number, since it uses less digits than its factorization.

840511881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8490036 (or 8490033 counting only the distinct ones).

The product of its (nonzero) digits is 10240, while the sum is 36.

The square root of 840511881 is about 28991.5829336723. The cubic root of 840511881 is about 943.7304157099.

The spelling of 840511881 in words is "eight hundred forty million, five hundred eleven thousand, eight hundred eighty-one".