21122530 has 32 divisors (see below), whose sum is σ = 44670528. Its totient is φ = 7089600.

The previous prime is 21122473. The next prime is 21122561. The reversal of 21122530 is 3522112.

It is a super-2 number, since 2×21122530² = 892322547201800, which contains 22 as substring.

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 15 ways as a sum of consecutive naturals, for example, 5956 + ... + 8815.

It is an arithmetic number, because the mean of its divisors is an integer number (1395954).

Almost surely, 2^21122530 is an apocalyptic number.

21122530 is an abundant number, since it is smaller than the sum of its proper divisors (23547998).

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

21122530 is a wasteful number, since it uses less digits than its factorization.

21122530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14802.

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 21122530 is about 4595.9253692809. The cubic root of 21122530 is about 276.4279662413.

Adding to 21122530 its reverse (3522112), we get a palindrome (24644642).

The spelling of 21122530 in words is "twenty-one million, one hundred twenty-two thousand, five hundred thirty".