19005869021 has 8 divisors (see below), whose sum is σ = 19662197688. Its totient is φ = 18358720000.

The previous prime is 19005868993. The next prime is 19005869041. The reversal of 19005869021 is 12096850091.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 6766872121 + 12238996900 = 82261^2 + 110630^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 19005869021 - 2³⁴ = 1825999837 is a prime.

It is a super-2 number, since 2×19005869021² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (41).

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 19005869021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19005869041) 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, 2290700 + ... + 2298981.

It is an arithmetic number, because the mean of its divisors is an integer number (2457774711).

Almost surely, 2^19005869021 is an apocalyptic number.

It is an amenable number.

19005869021 is a deficient number, since it is larger than the sum of its proper divisors (656328667).

19005869021 is a wasteful number, since it uses less digits than its factorization.

19005869021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4589823.

The product of its (nonzero) digits is 38880, while the sum is 41.

The spelling of 19005869021 in words is "nineteen billion, five million, eight hundred sixty-nine thousand, twenty-one".