19564945939984 has 15 divisors (see below), whose sum is σ = 37907117038767. Its totient is φ = 9782464123536.

The previous prime is 19564945939853. The next prime is 19564945939999. The reversal of 19564945939984 is 48993954946591.

The square root of 19564945939984 is 4423228.

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

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 17140009 + ... + 18245815.

Almost surely, 2^{19564945939984} is an apocalyptic number.

19564945939984 is the 4423228-th square number.

It is an amenable number.

19564945939984 is a deficient number, since it is larger than the sum of its proper divisors (18342171098783).

19564945939984 is an frugal number, since it uses more digits than its factorization.

19564945939984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2211622 (or 1105809 counting only the distinct ones).

The product of its digits is 13604889600, while the sum is 85.

The spelling of 19564945939984 in words is "nineteen trillion, five hundred sixty-four billion, nine hundred forty-five million, nine hundred thirty-nine thousand, nine hundred eighty-four".