21013130 has 8 divisors (see below), whose sum is σ = 37823652. Its totient is φ = 8405248.

The previous prime is 21013127. The next prime is 21013159. The reversal of 21013130 is 3131012.

It can be written as a sum of positive squares in 2 ways, for example, as 17330569 + 3682561 = 4163^2 + 1919^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1050647 + ... + 1050666.

Almost surely, 2^21013130 is an apocalyptic number.

21013130 is a deficient number, since it is larger than the sum of its proper divisors (16810522).

21013130 is a wasteful number, since it uses less digits than its factorization.

21013130 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2101320.

The product of its (nonzero) digits is 18, while the sum is 11.

The square root of 21013130 is about 4584.0080715461. The cubic root of 21013130 is about 275.9499051419.

Adding to 21013130 its reverse (3131012), we get a palindrome (24144142).

The spelling of 21013130 in words is "twenty-one million, thirteen thousand, one hundred thirty".