90121249087 has 2 divisors, whose sum is σ = 90121249088. Its totient is φ = 90121249086.

The previous prime is 90121249081. The next prime is 90121249181. The reversal of 90121249087 is 78094212109.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (78094212109) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 90121249087 - 2¹¹ = 90121247039 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90121249081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45060624543 + 45060624544.

It is an arithmetic number, because the mean of its divisors is an integer number (45060624544).

Almost surely, 2^90121249087 is an apocalyptic number.

90121249087 is a deficient number, since it is larger than the sum of its proper divisors (1).

90121249087 is an equidigital number, since it uses as much as digits as its factorization.

90121249087 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72576, while the sum is 43.

The spelling of 90121249087 in words is "ninety billion, one hundred twenty-one million, two hundred forty-nine thousand, eighty-seven".