21736230 has 32 divisors (see below), whose sum is σ = 52321248. Its totient is φ = 5779200.

The previous prime is 21736229. The next prime is 21736237. The reversal of 21736230 is 3263712.

It is a super-2 number, since 2×21736230² = 944927389225800, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21736230.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21736237) 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 15 ways as a sum of consecutive naturals, for example, 11770 + ... + 13490.

It is an arithmetic number, because the mean of its divisors is an integer number (1635039).

Almost surely, 2^21736230 is an apocalyptic number.

21736230 is an abundant number, since it is smaller than the sum of its proper divisors (30585018).

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

21736230 is a wasteful number, since it uses less digits than its factorization.

21736230 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2152.

The product of its (nonzero) digits is 1512, while the sum is 24.

The square root of 21736230 is about 4662.2129938474. The cubic root of 21736230 is about 279.0795882962.

Adding to 21736230 its reverse (3263712), we get a palindrome (24999942).

The spelling of 21736230 in words is "twenty-one million, seven hundred thirty-six thousand, two hundred thirty".