19890922391 has 4 divisors (see below), whose sum is σ = 19891240512. Its totient is φ = 19890604272.

The previous prime is 19890922319. The next prime is 19890922393. The reversal of 19890922391 is 19322909891.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 19890922391 - 2¹⁰ = 19890921367 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 (19890922393) 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, 30791 + ... + 201816.

It is an arithmetic number, because the mean of its divisors is an integer number (4972810128).

Almost surely, 2^19890922391 is an apocalyptic number.

19890922391 is a deficient number, since it is larger than the sum of its proper divisors (318121).

19890922391 is an equidigital number, since it uses as much as digits as its factorization.

19890922391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 318120.

The product of its (nonzero) digits is 629856, while the sum is 53.

The spelling of 19890922391 in words is "nineteen billion, eight hundred ninety million, nine hundred twenty-two thousand, three hundred ninety-one".