20774909 has 2 divisors, whose sum is σ = 20774910. Its totient is φ = 20774908.

The previous prime is 20774899. The next prime is 20774917. The reversal of 20774909 is 90947702.

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., 15038884 + 5736025 = 3878^2 + 2395^2 .

It is a cyclic number.

It is not a de Polignac number, because 20774909 - 2⁸ = 20774653 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 (20774939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10387454 + 10387455.

It is an arithmetic number, because the mean of its divisors is an integer number (10387455).

Almost surely, 2^20774909 is an apocalyptic number.

It is an amenable number.

20774909 is a deficient number, since it is larger than the sum of its proper divisors (1).

20774909 is an equidigital number, since it uses as much as digits as its factorization.

20774909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 31752, while the sum is 38.

The square root of 20774909 is about 4557.9500874845. The cubic root of 20774909 is about 274.9031460577.

The spelling of 20774909 in words is "twenty million, seven hundred seventy-four thousand, nine hundred nine".