19488525405561 has 99 divisors (see below), whose sum is σ = 30105361377903. Its totient is φ = 12615459832080.

The previous prime is 19488525405541. The next prime is 19488525405563. The reversal of 19488525405561 is 16550452588491.

It is a happy number.

The square root of 19488525405561 is 4414581.

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

19488525405561 is a `hidden beast` number, since 1 + 9 + 4 + 8 + 8 + 5 + 25 + 40 + 5 + 561 = 666.

It can be written as a sum of positive squares in only one way, i.e., 17438600162025 + 2049925243536 = 4175955^2 + 1431756^2 .

It is not a de Polignac number, because 19488525405561 - 2²¹ = 19488523308409 is a prime.

It is not an unprimeable number, because it can be changed into a prime (19488525405563) by changing a digit.

It is a polite number, since it can be written in 98 ways as a sum of consecutive naturals, for example, 39691497526 + ... + 39691498016.

Almost surely, 2^{19488525405561} is an apocalyptic number.

19488525405561 is the 4414581-st square number.

19488525405561 is the 2207291-st centered octagonal number.

It is an amenable number.

19488525405561 is a deficient number, since it is larger than the sum of its proper divisors (10616835972342).

19488525405561 is an frugal number, since it uses more digits than its factorization.

19488525405561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1086 (or 531 counting only the distinct ones).

The product of its (nonzero) digits is 69120000, while the sum is 63.

The spelling of 19488525405561 in words is "nineteen trillion, four hundred eighty-eight billion, five hundred twenty-five million, four hundred five thousand, five hundred sixty-one".