21087930193 has 8 divisors (see below), whose sum is σ = 23007618720. Its totient is φ = 19168675680.

The previous prime is 21087930181. The next prime is 21087930221. The reversal of 21087930193 is 39103978012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21087930193 - 2¹⁷ = 21087799121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21087930133) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2388 + ... + 205381.

It is an arithmetic number, because the mean of its divisors is an integer number (2875952340).

Almost surely, 2^21087930193 is an apocalyptic number.

It is an amenable number.

21087930193 is a deficient number, since it is larger than the sum of its proper divisors (1919688527).

21087930193 is a wasteful number, since it uses less digits than its factorization.

21087930193 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 217007.

The product of its (nonzero) digits is 81648, while the sum is 43.

The spelling of 21087930193 in words is "twenty-one billion, eighty-seven million, nine hundred thirty thousand, one hundred ninety-three".