90908990909 has 4 divisors (see below), whose sum is σ = 99173444640. Its totient is φ = 82644537180.

The previous prime is 90908990839. The next prime is 90908990911. The reversal of 90908990909 is 90909980909.

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 a de Polignac number, because none of the positive numbers 2^k-90908990909 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90908990999) 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, 4132226849 + ... + 4132226870.

It is an arithmetic number, because the mean of its divisors is an integer number (24793361160).

Almost surely, 2^90908990909 is an apocalyptic number.

It is an amenable number.

90908990909 is a deficient number, since it is larger than the sum of its proper divisors (8264453731).

90908990909 is a wasteful number, since it uses less digits than its factorization.

90908990909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8264453730.

The product of its (nonzero) digits is 4251528, while the sum is 62.

The spelling of 90908990909 in words is "ninety billion, nine hundred eight million, nine hundred ninety thousand, nine hundred nine".