21142230 has 32 divisors (see below), whose sum is σ = 51702624. Its totient is φ = 5531136.

The previous prime is 21142223. The next prime is 21142243. The reversal of 21142230 is 3224112.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a Curzon number.

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, 5059 + ... + 8238.

It is an arithmetic number, because the mean of its divisors is an integer number (1615707).

Almost surely, 2^21142230 is an apocalyptic number.

21142230 is an abundant number, since it is smaller than the sum of its proper divisors (30560394).

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

21142230 is a wasteful number, since it uses less digits than its factorization.

21142230 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13360.

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 21142230 is about 4598.0680725713. The cubic root of 21142230 is about 276.5138767020.

Adding to 21142230 its reverse (3224112), we get a palindrome (24366342).

The spelling of 21142230 in words is "twenty-one million, one hundred forty-two thousand, two hundred thirty".