90561871 has 2 divisors, whose sum is σ = 90561872. Its totient is φ = 90561870.

The previous prime is 90561859. The next prime is 90561893. The reversal of 90561871 is 17816509.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-90561871 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 90561871.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90561841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45280935 + 45280936.

It is an arithmetic number, because the mean of its divisors is an integer number (45280936).

Almost surely, 2^90561871 is an apocalyptic number.

90561871 is a deficient number, since it is larger than the sum of its proper divisors (1).

90561871 is an equidigital number, since it uses as much as digits as its factorization.

90561871 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15120, while the sum is 37.

The square root of 90561871 is about 9516.4001071834. The cubic root of 90561871 is about 449.0711226398.

The spelling of 90561871 in words is "ninety million, five hundred sixty-one thousand, eight hundred seventy-one".