840856623 has 4 divisors (see below), whose sum is σ = 1121142168. Its totient is φ = 560571080.

The previous prime is 840856591. The next prime is 840856657. The reversal of 840856623 is 326658048.

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

It is a cyclic number.

It is not a de Polignac number, because 840856623 - 2⁵ = 840856591 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (840851623) 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, 140142768 + ... + 140142773.

It is an arithmetic number, because the mean of its divisors is an integer number (280285542).

Almost surely, 2^840856623 is an apocalyptic number.

840856623 is a deficient number, since it is larger than the sum of its proper divisors (280285545).

840856623 is a wasteful number, since it uses less digits than its factorization.

840856623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 280285544.

The product of its (nonzero) digits is 276480, while the sum is 42.

The square root of 840856623 is about 28997.5278773898. The cubic root of 840856623 is about 943.8594240153.

The spelling of 840856623 in words is "eight hundred forty million, eight hundred fifty-six thousand, six hundred twenty-three".