21275491208 has 32 divisors (see below), whose sum is σ = 41226831360. Its totient is φ = 10282477440.

The previous prime is 21275491189. The next prime is 21275491219. The reversal of 21275491208 is 80219457212.

It is a super-2 number, since 2×21275491208² (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 (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 162485 + ... + 262587.

It is an arithmetic number, because the mean of its divisors is an integer number (1288338480).

Almost surely, 2^21275491208 is an apocalyptic number.

It is an amenable number.

21275491208 is a deficient number, since it is larger than the sum of its proper divisors (19951340152).

21275491208 is a wasteful number, since it uses less digits than its factorization.

21275491208 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100997 (or 100993 counting only the distinct ones).

The product of its (nonzero) digits is 80640, while the sum is 41.

The spelling of 21275491208 in words is "twenty-one billion, two hundred seventy-five million, four hundred ninety-one thousand, two hundred eight".