19902190209 has 32 divisors (see below), whose sum is σ = 30221769600. Its totient is φ = 11539100160.

The previous prime is 19902190199. The next prime is 19902190211. The reversal of 19902190209 is 90209120991.

It is not a de Polignac number, because 19902190209 - 2⁵ = 19902190177 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (19902190409) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8917 + ... + 199709.

It is an arithmetic number, because the mean of its divisors is an integer number (944430300).

Almost surely, 2^19902190209 is an apocalyptic number.

It is an amenable number.

19902190209 is a deficient number, since it is larger than the sum of its proper divisors (10319579391).

19902190209 is a wasteful number, since it uses less digits than its factorization.

19902190209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 190945.

The product of its (nonzero) digits is 26244, while the sum is 42.

The spelling of 19902190209 in words is "nineteen billion, nine hundred two million, one hundred ninety thousand, two hundred nine".