19850454989 has 4 divisors (see below), whose sum is σ = 19853345856. Its totient is φ = 19847564124.

The previous prime is 19850454979. The next prime is 19850455043. The reversal of 19850454989 is 98945405891.

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-19850454989 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 (19850454979) 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, 1435109 + ... + 1448874.

It is an arithmetic number, because the mean of its divisors is an integer number (4963336464).

Almost surely, 2^19850454989 is an apocalyptic number.

It is an amenable number.

19850454989 is a deficient number, since it is larger than the sum of its proper divisors (2890867).

19850454989 is an equidigital number, since it uses as much as digits as its factorization.

19850454989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2890866.

The product of its (nonzero) digits is 18662400, while the sum is 62.

The spelling of 19850454989 in words is "nineteen billion, eight hundred fifty million, four hundred fifty-four thousand, nine hundred eighty-nine".