21330131 has 4 divisors (see below), whose sum is σ = 22257552. Its totient is φ = 20402712.

The previous prime is 21330119. The next prime is 21330149. The reversal of 21330131 is 13103312.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21330131 - 2¹⁰ = 21329107 is a prime.

It is a super-2 number, since 2×21330131² = 909948976954322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21330161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 463676 + ... + 463721.

It is an arithmetic number, because the mean of its divisors is an integer number (5564388).

Almost surely, 2^21330131 is an apocalyptic number.

21330131 is a deficient number, since it is larger than the sum of its proper divisors (927421).

21330131 is an equidigital number, since it uses as much as digits as its factorization.

21330131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 927420.

The product of its (nonzero) digits is 54, while the sum is 14.

The square root of 21330131 is about 4618.4554777544. The cubic root of 21330131 is about 277.3306317088.

Adding to 21330131 its reverse (13103312), we get a palindrome (34433443).

The spelling of 21330131 in words is "twenty-one million, three hundred thirty thousand, one hundred thirty-one".