19471132521 has 27 divisors (see below), whose sum is σ = 28389245157. Its totient is φ = 12859914240.

The previous prime is 19471132481. The next prime is 19471132523. The reversal of 19471132521 is 12523117491.

It is a happy number.

The square root of 19471132521 is 139539.

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

19471132521 is a `hidden beast` number, since 1 + 9 + 471 + 132 + 52 + 1 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 837225 + 19470295296 = 915^2 + 139536^2 .

It is not a de Polignac number, because 19471132521 - 2¹⁷ = 19471001449 is a prime.

It is not an unprimeable number, because it can be changed into a prime (19471132523) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 80792961 + ... + 80793201.

Almost surely, 2^19471132521 is an apocalyptic number.

19471132521 is the 139539-th square number.

19471132521 is the 69770-th centered octagonal number.

It is an amenable number.

19471132521 is a deficient number, since it is larger than the sum of its proper divisors (8918112636).

19471132521 is an frugal number, since it uses more digits than its factorization.

19471132521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 874 (or 437 counting only the distinct ones).

The product of its digits is 15120, while the sum is 36.

Multiplying 19471132521 by its sum of digits (36), we get a square (700960770756 = 837234²).

The spelling of 19471132521 in words is "nineteen billion, four hundred seventy-one million, one hundred thirty-two thousand, five hundred twenty-one".