19621921193 has 16 divisors (see below), whose sum is σ = 22740713856. Its totient is φ = 16582216320.

The previous prime is 19621921139. The next prime is 19621921213. The reversal of 19621921193 is 39112912691.

It is a cyclic number.

It is not a de Polignac number, because 19621921193 - 2¹² = 19621917097 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (19621921103) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1824530 + ... + 1835252.

It is an arithmetic number, because the mean of its divisors is an integer number (1421294616).

Almost surely, 2^19621921193 is an apocalyptic number.

It is an amenable number.

19621921193 is a deficient number, since it is larger than the sum of its proper divisors (3118792663).

19621921193 is a wasteful number, since it uses less digits than its factorization.

19621921193 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14384.

The product of its digits is 52488, while the sum is 44.

The spelling of 19621921193 in words is "nineteen billion, six hundred twenty-one million, nine hundred twenty-one thousand, one hundred ninety-three".