19517487025 has 9 divisors (see below), whose sum is σ = 24202550113. Its totient is φ = 15613430800.

The previous prime is 19517486977. The next prime is 19517487037. The reversal of 19517487025 is 52078471591.

The square root of 19517487025 is 139705.

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

It can be written as a sum of positive squares in 4 ways, for example, as 466862449 + 19050624576 = 21607^2 + 138024^2 .

It is not a de Polignac number, because 19517487025 - 2⁷ = 19517486897 is a prime.

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 19517487025.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 684555 + ... + 712495.

Almost surely, 2^19517487025 is an apocalyptic number.

19517487025 is the 139705-th square number.

19517487025 is the 69853-rd centered octagonal number.

It is an amenable number.

19517487025 is a deficient number, since it is larger than the sum of its proper divisors (4685063088).

19517487025 is an frugal number, since it uses more digits than its factorization.

19517487025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55892 (or 27946 counting only the distinct ones).

The product of its (nonzero) digits is 705600, while the sum is 49.

Multiplying 19517487025 by its sum of digits (49), we get a square (956356864225 = 977935²).

The spelling of 19517487025 in words is "nineteen billion, five hundred seventeen million, four hundred eighty-seven thousand, twenty-five".