840550831 has 2 divisors, whose sum is σ = 840550832. Its totient is φ = 840550830.

The previous prime is 840550829. The next prime is 840550849. The reversal of 840550831 is 138055048.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 840550831 - 2¹ = 840550829 is a prime.

It is a super-2 number, since 2×840550831² = 1413051398989581122, which contains 22 as substring.

Together with 840550829, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (840550871) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 420275415 + 420275416.

It is an arithmetic number, because the mean of its divisors is an integer number (420275416).

Almost surely, 2^840550831 is an apocalyptic number.

840550831 is a deficient number, since it is larger than the sum of its proper divisors (1).

840550831 is an equidigital number, since it uses as much as digits as its factorization.

840550831 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 19200, while the sum is 34.

The square root of 840550831 is about 28992.2546725845. The cubic root of 840550831 is about 943.7449932281.

The spelling of 840550831 in words is "eight hundred forty million, five hundred fifty thousand, eight hundred thirty-one".