20749229 has 2 divisors, whose sum is σ = 20749230. Its totient is φ = 20749228.

The previous prime is 20749213. The next prime is 20749241. The reversal of 20749229 is 92294702.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19802500 + 946729 = 4450^2 + 973^2 .

It is a cyclic number.

It is not a de Polignac number, because 20749229 - 2⁴ = 20749213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20749259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10374614 + 10374615.

It is an arithmetic number, because the mean of its divisors is an integer number (10374615).

Almost surely, 2^20749229 is an apocalyptic number.

It is an amenable number.

20749229 is a deficient number, since it is larger than the sum of its proper divisors (1).

20749229 is an equidigital number, since it uses as much as digits as its factorization.

20749229 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18144, while the sum is 35.

The square root of 20749229 is about 4555.1321605416. The cubic root of 20749229 is about 274.7898294994.

The spelling of 20749229 in words is "twenty million, seven hundred forty-nine thousand, two hundred twenty-nine".