21130307 has 16 divisors (see below), whose sum is σ = 24579072. Its totient is φ = 17973120.

The previous prime is 21130301. The next prime is 21130321. The reversal of 21130307 is 70303112.

It is not a de Polignac number, because 21130307 - 2²⁴ = 4353091 is a prime.

It is a super-3 number, since 3×21130307³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21130301) 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, 11003 + ... + 12779.

It is an arithmetic number, because the mean of its divisors is an integer number (1536192).

Almost surely, 2^21130307 is an apocalyptic number.

21130307 is a deficient number, since it is larger than the sum of its proper divisors (3448765).

21130307 is a wasteful number, since it uses less digits than its factorization.

21130307 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1858.

The product of its (nonzero) digits is 126, while the sum is 17.

The square root of 21130307 is about 4596.7713669488. The cubic root of 21130307 is about 276.4618876277.

Adding to 21130307 its reverse (70303112), we get a palindrome (91433419).

The spelling of 21130307 in words is "twenty-one million, one hundred thirty thousand, three hundred seven".