21690745175 has 12 divisors (see below), whose sum is σ = 29341662936. Its totient is φ = 15775087200.

The previous prime is 21690745147. The next prime is 21690745183. The reversal of 21690745175 is 57154709612.

It is not a de Polignac number, because 21690745175 - 2¹⁰ = 21690744151 is a prime.

It is a Duffinian number.

It is a congruent number.

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 11 ways as a sum of consecutive naturals, for example, 39437444 + ... + 39437993.

It is an arithmetic number, because the mean of its divisors is an integer number (2445138578).

Almost surely, 2^21690745175 is an apocalyptic number.

21690745175 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21690745175 is a deficient number, since it is larger than the sum of its proper divisors (7650917761).

21690745175 is a wasteful number, since it uses less digits than its factorization.

21690745175 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78875458 (or 78875453 counting only the distinct ones).

The product of its (nonzero) digits is 529200, while the sum is 47.

The spelling of 21690745175 in words is "twenty-one billion, six hundred ninety million, seven hundred forty-five thousand, one hundred seventy-five".