21123063 has 12 divisors (see below), whose sum is σ = 32858280. Its totient is φ = 12998736.

The previous prime is 21123043. The next prime is 21123073. The reversal of 21123063 is 36032112.

It is a de Polignac number, because none of the positive numbers 2^k-21123063 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21123013) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 90153 + ... + 90386.

It is an arithmetic number, because the mean of its divisors is an integer number (2738190).

Almost surely, 2^21123063 is an apocalyptic number.

21123063 is a deficient number, since it is larger than the sum of its proper divisors (11735217).

21123063 is a wasteful number, since it uses less digits than its factorization.

21123063 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 180558 (or 180555 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

The square root of 21123063 is about 4595.9833550612. The cubic root of 21123063 is about 276.4302913237.

Adding to 21123063 its reverse (36032112), we get a palindrome (57155175).

The spelling of 21123063 in words is "twenty-one million, one hundred twenty-three thousand, sixty-three".