19666077849 has 36 divisors (see below), whose sum is σ = 32581331328. Its totient is φ = 11400610320.

The previous prime is 19666077839. The next prime is 19666077913. The reversal of 19666077849 is 94877066691.

It is not a de Polignac number, because 19666077849 - 2⁷ = 19666077721 is a prime.

It is not an unprimeable number, because it can be changed into a prime (19666077839) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 367537 + ... + 417630.

Almost surely, 2^19666077849 is an apocalyptic number.

It is an amenable number.

19666077849 is a deficient number, since it is larger than the sum of its proper divisors (12915253479).

19666077849 is a wasteful number, since it uses less digits than its factorization.

19666077849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 785218 (or 785204 counting only the distinct ones).

The product of its (nonzero) digits is 27433728, while the sum is 63.

The spelling of 19666077849 in words is "nineteen billion, six hundred sixty-six million, seventy-seven thousand, eight hundred forty-nine".