19587961849 has 9 divisors (see below), whose sum is σ = 19726224973. Its totient is φ = 19450664032.

The previous prime is 19587961837. The next prime is 19587961919. The reversal of 19587961849 is 94816978591.

The square root of 19587961849 is 139957.

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 12248955625 + 7339006224 = 110675^2 + 85668^2 .

It is a de Polignac number, because none of the positive numbers 2^k-19587961849 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19587961249) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 24212157 + ... + 24212965.

Almost surely, 2^19587961849 is an apocalyptic number.

19587961849 is the 139957-th square number.

19587961849 is the 69979-th centered octagonal number.

It is an amenable number.

19587961849 is a deficient number, since it is larger than the sum of its proper divisors (138263124).

19587961849 is an frugal number, since it uses more digits than its factorization.

19587961849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1964 (or 982 counting only the distinct ones).

The product of its digits is 39191040, while the sum is 67.

The spelling of 19587961849 in words is "nineteen billion, five hundred eighty-seven million, nine hundred sixty-one thousand, eight hundred forty-nine".