20390911091 has 8 divisors (see below), whose sum is σ = 20787822768. Its totient is φ = 19996020000.

The previous prime is 20390911067. The next prime is 20390911139. The reversal of 20390911091 is 19011909302.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20390911091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20390911391) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 484760 + ... + 525141.

It is an arithmetic number, because the mean of its divisors is an integer number (2598477846).

Almost surely, 2^20390911091 is an apocalyptic number.

20390911091 is a deficient number, since it is larger than the sum of its proper divisors (396911677).

20390911091 is a wasteful number, since it uses less digits than its factorization.

20390911091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1010293.

The product of its (nonzero) digits is 4374, while the sum is 35.

The spelling of 20390911091 in words is "twenty billion, three hundred ninety million, nine hundred eleven thousand, ninety-one".