21797108975 has 12 divisors (see below), whose sum is σ = 27486525720. Its totient is φ = 17142132000.

The previous prime is 21797108969. The next prime is 21797108987. The reversal of 21797108975 is 57980179712.

It is a happy number.

It is not a de Polignac number, because 21797108975 - 2¹⁰ = 21797107951 is a prime.

It is a super-2 number, since 2×21797108975² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21797108975.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7387376 + ... + 7390325.

It is an arithmetic number, because the mean of its divisors is an integer number (2290543810).

Almost surely, 2^21797108975 is an apocalyptic number.

21797108975 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21797108975 is a deficient number, since it is larger than the sum of its proper divisors (5689416745).

21797108975 is a wasteful number, since it uses less digits than its factorization.

21797108975 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14777770 (or 14777765 counting only the distinct ones).

The product of its (nonzero) digits is 2222640, while the sum is 56.

The spelling of 21797108975 in words is "twenty-one billion, seven hundred ninety-seven million, one hundred eight thousand, nine hundred seventy-five".