21129230 has 8 divisors (see below), whose sum is σ = 38032632. Its totient is φ = 8451688.

The previous prime is 21129221. The next prime is 21129239. The reversal of 21129230 is 3292112.

It is an interprime number because it is at equal distance from previous prime (21129221) and next prime (21129239).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21129239) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1056452 + ... + 1056471.

It is an arithmetic number, because the mean of its divisors is an integer number (4754079).

Almost surely, 2^21129230 is an apocalyptic number.

21129230 is a deficient number, since it is larger than the sum of its proper divisors (16903402).

21129230 is a wasteful number, since it uses less digits than its factorization.

21129230 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2112930.

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 21129230 is about 4596.6542180155. The cubic root of 21129230 is about 276.4571905117.

The spelling of 21129230 in words is "twenty-one million, one hundred twenty-nine thousand, two hundred thirty".