21193639212 has 24 divisors (see below), whose sum is σ = 49941449712. Its totient is φ = 6994600000.

The previous prime is 21193639199. The next prime is 21193639219. The reversal of 21193639212 is 21293639112.

It is a hoax number, since the sum of its digits (39) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (21193639219) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8742039 + ... + 8744462.

It is an arithmetic number, because the mean of its divisors is an integer number (2080893738).

Almost surely, 2^21193639212 is an apocalyptic number.

It is an amenable number.

21193639212 is an abundant number, since it is smaller than the sum of its proper divisors (28747810500).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21193639212 is a wasteful number, since it uses less digits than its factorization.

21193639212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17486609 (or 17486607 counting only the distinct ones).

The product of its digits is 34992, while the sum is 39.

The spelling of 21193639212 in words is "twenty-one billion, one hundred ninety-three million, six hundred thirty-nine thousand, two hundred twelve".