20829281 has 8 divisors (see below), whose sum is σ = 22864224. Its totient is φ = 18817920.

The previous prime is 20829269. The next prime is 20829313. The reversal of 20829281 is 18292802.

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

It is not a de Polignac number, because 20829281 - 2⁶ = 20829217 is a prime.

It is a super-2 number, since 2×20829281² = 867717893953922, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20829251) 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, 4016 + ... + 7601.

It is an arithmetic number, because the mean of its divisors is an integer number (2858028).

Almost surely, 2^20829281 is an apocalyptic number.

It is an amenable number.

20829281 is a deficient number, since it is larger than the sum of its proper divisors (2034943).

20829281 is a wasteful number, since it uses less digits than its factorization.

20829281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11791.

The product of its (nonzero) digits is 4608, while the sum is 32.

The square root of 20829281 is about 4563.9107134123. The cubic root of 20829281 is about 275.1427622379.

The spelling of 20829281 in words is "twenty million, eight hundred twenty-nine thousand, two hundred eighty-one".