21830129 has 4 divisors (see below), whose sum is σ = 22042176. Its totient is φ = 21618084.

The previous prime is 21830119. The next prime is 21830143. The reversal of 21830129 is 92103812.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21830129 - 2¹² = 21826033 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21830098 and 21830107.

It is not an unprimeable number, because it can be changed into a prime (21830119) 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 3 ways as a sum of consecutive naturals, for example, 105869 + ... + 106074.

It is an arithmetic number, because the mean of its divisors is an integer number (5510544).

Almost surely, 2^21830129 is an apocalyptic number.

It is an amenable number.

21830129 is a deficient number, since it is larger than the sum of its proper divisors (212047).

21830129 is a wasteful number, since it uses less digits than its factorization.

21830129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212046.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 21830129 is about 4672.2723593558. The cubic root of 21830129 is about 279.4808791295.

The spelling of 21830129 in words is "twenty-one million, eight hundred thirty thousand, one hundred twenty-nine".