21286230 has 32 divisors (see below), whose sum is σ = 58385664. Its totient is φ = 4865376.

The previous prime is 21286229. The next prime is 21286241. The reversal of 21286230 is 3268212.

It is a super-4 number, since 4×21286230⁴ (a number of 30 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21286230.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 50472 + ... + 50891.

It is an arithmetic number, because the mean of its divisors is an integer number (1824552).

Almost surely, 2^21286230 is an apocalyptic number.

21286230 is an abundant number, since it is smaller than the sum of its proper divisors (37099434).

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

21286230 is a wasteful number, since it uses less digits than its factorization.

21286230 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101380.

The product of its (nonzero) digits is 1152, while the sum is 24.

The square root of 21286230 is about 4613.7002503414. The cubic root of 21286230 is about 277.1402366534.

The spelling of 21286230 in words is "twenty-one million, two hundred eighty-six thousand, two hundred thirty".