20829749 has 2 divisors, whose sum is σ = 20829750. Its totient is φ = 20829748.

The previous prime is 20829727. The next prime is 20829821. The reversal of 20829749 is 94792802.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19518724 + 1311025 = 4418^2 + 1145^2 .

It is a cyclic number.

It is not a de Polignac number, because 20829749 - 2⁸ = 20829493 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20829349) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10414874 + 10414875.

It is an arithmetic number, because the mean of its divisors is an integer number (10414875).

Almost surely, 2^20829749 is an apocalyptic number.

It is an amenable number.

20829749 is a deficient number, since it is larger than the sum of its proper divisors (1).

20829749 is an equidigital number, since it uses as much as digits as its factorization.

20829749 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72576, while the sum is 41.

The square root of 20829749 is about 4563.9619849425. The cubic root of 20829749 is about 275.1448228923.

The spelling of 20829749 in words is "twenty million, eight hundred twenty-nine thousand, seven hundred forty-nine".