20829221 has 8 divisors (see below), whose sum is σ = 24625920. Its totient is φ = 17237808.

The previous prime is 20829217. The next prime is 20829223. The reversal of 20829221 is 12292802.

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

It is not a de Polignac number, because 20829221 - 2² = 20829217 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20829223) 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 7 ways as a sum of consecutive naturals, for example, 51101 + ... + 51506.

It is an arithmetic number, because the mean of its divisors is an integer number (3078240).

Almost surely, 2^20829221 is an apocalyptic number.

It is an amenable number.

20829221 is a deficient number, since it is larger than the sum of its proper divisors (3796699).

20829221 is a wasteful number, since it uses less digits than its factorization.

20829221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102643.

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 20829221 is about 4563.9041400976. The cubic root of 20829221 is about 275.1424980492.

The spelling of 20829221 in words is "twenty million, eight hundred twenty-nine thousand, two hundred twenty-one".