21105097175 has 6 divisors (see below), whose sum is σ = 26170320528. Its totient is φ = 16884077720.

The previous prime is 21105097171. The next prime is 21105097177. The reversal of 21105097175 is 57179050112.

It is a happy number.

It is not a de Polignac number, because 21105097175 - 2² = 21105097171 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21105097171) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 422101919 + ... + 422101968.

It is an arithmetic number, because the mean of its divisors is an integer number (4361720088).

Almost surely, 2^21105097175 is an apocalyptic number.

21105097175 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21105097175 is a deficient number, since it is larger than the sum of its proper divisors (5065223353).

21105097175 is an equidigital number, since it uses as much as digits as its factorization.

21105097175 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 844203897 (or 844203892 counting only the distinct ones).

The product of its (nonzero) digits is 22050, while the sum is 38.

The spelling of 21105097175 in words is "twenty-one billion, one hundred five million, ninety-seven thousand, one hundred seventy-five".