90899073521 has 2 divisors, whose sum is σ = 90899073522. Its totient is φ = 90899073520.

The previous prime is 90899073439. The next prime is 90899073523. The reversal of 90899073521 is 12537099809.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 74603274496 + 16295799025 = 273136^2 + 127655^2 .

It is a cyclic number.

It is not a de Polignac number, because 90899073521 - 2¹⁰ = 90899072497 is a prime.

Together with 90899073523, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (90899073523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45449536760 + 45449536761.

It is an arithmetic number, because the mean of its divisors is an integer number (45449536761).

Almost surely, 2^90899073521 is an apocalyptic number.

It is an amenable number.

90899073521 is a deficient number, since it is larger than the sum of its proper divisors (1).

90899073521 is an equidigital number, since it uses as much as digits as its factorization.

90899073521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1224720, while the sum is 53.

The spelling of 90899073521 in words is "ninety billion, eight hundred ninety-nine million, seventy-three thousand, five hundred twenty-one".