21052130 has 64 divisors (see below), whose sum is σ = 44229888. Its totient is φ = 7138560.

The previous prime is 21052127. The next prime is 21052159. The reversal of 21052130 is 3125012.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 134012 + ... + 134168.

It is an arithmetic number, because the mean of its divisors is an integer number (691092).

Almost surely, 2^21052130 is an apocalyptic number.

21052130 is an abundant number, since it is smaller than the sum of its proper divisors (23177758).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21052130 is a wasteful number, since it uses less digits than its factorization.

21052130 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 251.

The product of its (nonzero) digits is 60, while the sum is 14.

The square root of 21052130 is about 4588.2600187871. The cubic root of 21052130 is about 276.1205190247.

Adding to 21052130 its reverse (3125012), we get a palindrome (24177142).

The spelling of 21052130 in words is "twenty-one million, fifty-two thousand, one hundred thirty".