81889007 has 2 divisors, whose sum is σ = 81889008. Its totient is φ = 81889006.

The previous prime is 81888973. The next prime is 81889019. The reversal of 81889007 is 70098818.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81889007 - 2⁶ = 81888943 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81889037) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40944503 + 40944504.

It is an arithmetic number, because the mean of its divisors is an integer number (40944504).

Almost surely, 2^81889007 is an apocalyptic number.

81889007 is a deficient number, since it is larger than the sum of its proper divisors (1).

81889007 is an equidigital number, since it uses as much as digits as its factorization.

81889007 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32256, while the sum is 41.

The square root of 81889007 is about 9049.2544996812. The cubic root of 81889007 is about 434.2520409489.

The spelling of 81889007 in words is "eighty-one million, eight hundred eighty-nine thousand, seven".