20829409 has 8 divisors (see below), whose sum is σ = 21526848. Its totient is φ = 20139120.

The previous prime is 20829349. The next prime is 20829433. The reversal of 20829409 is 90492802.

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

It is a cyclic number.

It is not a de Polignac number, because 20829409 - 2⁹ = 20828897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20829449) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4494 + ... + 7864.

It is an arithmetic number, because the mean of its divisors is an integer number (2690856).

Almost surely, 2^20829409 is an apocalyptic number.

It is an amenable number.

20829409 is a deficient number, since it is larger than the sum of its proper divisors (697439).

20829409 is a wasteful number, since it uses less digits than its factorization.

20829409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3575.

The product of its (nonzero) digits is 10368, while the sum is 34.

The square root of 20829409 is about 4563.9247364522. The cubic root of 20829409 is about 275.1433258387.

The spelling of 20829409 in words is "twenty million, eight hundred twenty-nine thousand, four hundred nine".