21175715755 has 16 divisors (see below), whose sum is σ = 27135072000. Its totient is φ = 15828785280.

The previous prime is 21175715747. The next prime is 21175715761. The reversal of 21175715755 is 55751757112.

It is not a de Polignac number, because 21175715755 - 2³ = 21175715747 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2350980 + ... + 2359969.

It is an arithmetic number, because the mean of its divisors is an integer number (1695942000).

Almost surely, 2^21175715755 is an apocalyptic number.

21175715755 is a deficient number, since it is larger than the sum of its proper divisors (5959356245).

21175715755 is a wasteful number, since it uses less digits than its factorization.

21175715755 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4711014.

The product of its digits is 428750, while the sum is 46.

The spelling of 21175715755 in words is "twenty-one billion, one hundred seventy-five million, seven hundred fifteen thousand, seven hundred fifty-five".