90121908013 has 4 divisors (see below), whose sum is σ = 93029066368. Its totient is φ = 87214749660.

The previous prime is 90121907933. The next prime is 90121908047. The reversal of 90121908013 is 31080912109.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 90121908013 - 2⁹ = 90121907501 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 90121908013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90121908073) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1453579131 + ... + 1453579192.

It is an arithmetic number, because the mean of its divisors is an integer number (23257266592).

Almost surely, 2^90121908013 is an apocalyptic number.

It is an amenable number.

90121908013 is a deficient number, since it is larger than the sum of its proper divisors (2907158355).

90121908013 is a wasteful number, since it uses less digits than its factorization.

90121908013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2907158354.

The product of its (nonzero) digits is 3888, while the sum is 34.

The spelling of 90121908013 in words is "ninety billion, one hundred twenty-one million, nine hundred eight thousand, thirteen".