21021223195 has 20 divisors (see below), whose sum is σ = 29427978240. Its totient is φ = 14414544816.

The previous prime is 21021223183. The next prime is 21021223213. The reversal of 21021223195 is 59132212012.

It is not a de Polignac number, because 21021223195 - 2⁹ = 21021222683 is a prime.

It is a super-2 number, since 2×21021223195² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

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 19 ways as a sum of consecutive naturals, for example, 863515 + ... + 887524.

It is an arithmetic number, because the mean of its divisors is an integer number (1471398912).

Almost surely, 2^21021223195 is an apocalyptic number.

21021223195 is a deficient number, since it is larger than the sum of its proper divisors (8406755045).

21021223195 is an frugal number, since it uses more digits than its factorization.

21021223195 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1751072 (or 1751051 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 28.

The spelling of 21021223195 in words is "twenty-one billion, twenty-one million, two hundred twenty-three thousand, one hundred ninety-five".