19633894641 has 15 divisors (see below), whose sum is σ = 29331529051. Its totient is φ = 13088422368.

The previous prime is 19633894607. The next prime is 19633894669. The reversal of 19633894641 is 14649833691.

The square root of 19633894641 is 140121.

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

It can be written as a sum of positive squares in only one way, i.e., 7339520241 + 12294374400 = 85671^2 + 110880^2 .

It is not a de Polignac number, because 19633894641 - 2²⁷ = 19499676913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19633894681) by changing a digit.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 1253305 + ... + 1268873.

Almost surely, 2^19633894641 is an apocalyptic number.

19633894641 is the 140121-st square number.

19633894641 is the 70061-st centered octagonal number.

It is an amenable number.

19633894641 is a deficient number, since it is larger than the sum of its proper divisors (9697634410).

19633894641 is an frugal number, since it uses more digits than its factorization.

19633894641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31150 (or 15572 counting only the distinct ones).

The product of its digits is 3359232, while the sum is 54.

The spelling of 19633894641 in words is "nineteen billion, six hundred thirty-three million, eight hundred ninety-four thousand, six hundred forty-one".