21125670163 has 16 divisors (see below), whose sum is σ = 23961611520. Its totient is φ = 18463869216.

The previous prime is 21125670157. The next prime is 21125670271. The reversal of 21125670163 is 36107652112.

It is not a de Polignac number, because 21125670163 - 2²⁹ = 20588799251 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21125670563) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 433056 + ... + 479362.

It is an arithmetic number, because the mean of its divisors is an integer number (1497600720).

Almost surely, 2^21125670163 is an apocalyptic number.

21125670163 is a deficient number, since it is larger than the sum of its proper divisors (2835941357).

21125670163 is a wasteful number, since it uses less digits than its factorization.

21125670163 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48186.

The product of its (nonzero) digits is 15120, while the sum is 34.

The spelling of 21125670163 in words is "twenty-one billion, one hundred twenty-five million, six hundred seventy thousand, one hundred sixty-three".