19485088921 has 3 divisors (see below), whose sum is σ = 19485228511. Its totient is φ = 19484949332.

The previous prime is 19485088823. The next prime is 19485088937. The reversal of 19485088921 is 12988058491.

The square root of 19485088921 is 139589.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 16845184521 + 2639904400 = 129789^2 + 51380^2 .

It is not a de Polignac number, because 19485088921 - 2²⁵ = 19451534489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19485088321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 69795 + ... + 209383.

Almost surely, 2^19485088921 is an apocalyptic number.

19485088921 is the 139589-th square number.

19485088921 is the 69795-th centered octagonal number.

It is an amenable number.

19485088921 is a deficient number, since it is larger than the sum of its proper divisors (139590).

19485088921 is an frugal number, since it uses more digits than its factorization.

19485088921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 279178 (or 139589 counting only the distinct ones).

The product of its (nonzero) digits is 1658880, while the sum is 55.

The spelling of 19485088921 in words is "nineteen billion, four hundred eighty-five million, eighty-eight thousand, nine hundred twenty-one".