21130023 has 8 divisors (see below), whose sum is σ = 28317168. Its totient is φ = 14014784.

The previous prime is 21130001. The next prime is 21130027. The reversal of 21130023 is 32003112.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21130023 - 2⁶ = 21129959 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21129990 and 21130008.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21130027) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17286 + ... + 18467.

It is an arithmetic number, because the mean of its divisors is an integer number (3539646).

Almost surely, 2^21130023 is an apocalyptic number.

21130023 is a deficient number, since it is larger than the sum of its proper divisors (7187145).

21130023 is a wasteful number, since it uses less digits than its factorization.

21130023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35953.

The product of its (nonzero) digits is 36, while the sum is 12.

The square root of 21130023 is about 4596.7404755979. The cubic root of 21130023 is about 276.4606490351.

Adding to 21130023 its reverse (32003112), we get a palindrome (53133135).

The spelling of 21130023 in words is "twenty-one million, one hundred thirty thousand, twenty-three".