20764109 has 2 divisors, whose sum is σ = 20764110. Its totient is φ = 20764108.

The previous prime is 20764103. The next prime is 20764127. The reversal of 20764109 is 90146702.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13118884 + 7645225 = 3622^2 + 2765^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20764109 is a prime.

It is a super-2 number, since 2×20764109² = 862296445127762, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20764103) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10382054 + 10382055.

It is an arithmetic number, because the mean of its divisors is an integer number (10382055).

Almost surely, 2^20764109 is an apocalyptic number.

It is an amenable number.

20764109 is a deficient number, since it is larger than the sum of its proper divisors (1).

20764109 is an equidigital number, since it uses as much as digits as its factorization.

20764109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3024, while the sum is 29.

The square root of 20764109 is about 4556.7651903516. The cubic root of 20764109 is about 274.8555009456.

The spelling of 20764109 in words is "twenty million, seven hundred sixty-four thousand, one hundred nine".