890442991 has 2 divisors, whose sum is σ = 890442992. Its totient is φ = 890442990.

The previous prime is 890442929. The next prime is 890443013. The reversal of 890442991 is 199244098.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 890442991 - 2⁷ = 890442863 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (890142991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 445221495 + 445221496.

It is an arithmetic number, because the mean of its divisors is an integer number (445221496).

Almost surely, 2^890442991 is an apocalyptic number.

890442991 is a deficient number, since it is larger than the sum of its proper divisors (1).

890442991 is an equidigital number, since it uses as much as digits as its factorization.

890442991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 186624, while the sum is 46.

The square root of 890442991 is about 29840.2914027326. The cubic root of 890442991 is about 962.0597380647.

The spelling of 890442991 in words is "eight hundred ninety million, four hundred forty-two thousand, nine hundred ninety-one".