21130539 has 8 divisors (see below), whose sum is σ = 28861392. Its totient is φ = 13743360.

The previous prime is 21130511. The next prime is 21130573. The reversal of 21130539 is 93503112.

It is a happy number.

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

It is not a de Polignac number, because 21130539 - 2⁹ = 21130027 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21130939) 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, 85774 + ... + 86019.

It is an arithmetic number, because the mean of its divisors is an integer number (3607674).

Almost surely, 2^21130539 is an apocalyptic number.

21130539 is a deficient number, since it is larger than the sum of its proper divisors (7730853).

21130539 is a wasteful number, since it uses less digits than its factorization.

21130539 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171837.

The product of its (nonzero) digits is 810, while the sum is 24.

The square root of 21130539 is about 4596.7966019827. The cubic root of 21130539 is about 276.4628994276.

The spelling of 21130539 in words is "twenty-one million, one hundred thirty thousand, five hundred thirty-nine".