19985759641 has 3 divisors (see below), whose sum is σ = 19985901013. Its totient is φ = 19985618270.

The previous prime is 19985759639. The next prime is 19985759701. The reversal of 19985759641 is 14695758991.

The square root of 19985759641 is 141371.

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

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 19985759641 - 2¹ = 19985759639 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19985759611) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 70686 + ... + 212056.

Almost surely, 2^19985759641 is an apocalyptic number.

19985759641 is the 141371-st square number.

19985759641 is the 70686-th centered octagonal number.

It is an amenable number.

19985759641 is a deficient number, since it is larger than the sum of its proper divisors (141372).

19985759641 is an frugal number, since it uses more digits than its factorization.

19985759641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 282742 (or 141371 counting only the distinct ones).

The product of its digits is 24494400, while the sum is 64.

Multiplying 19985759641 by its sum of digits (64), we get a square (1279088617024 = 1130968²).

The spelling of 19985759641 in words is "nineteen billion, nine hundred eighty-five million, seven hundred fifty-nine thousand, six hundred forty-one".