20302409 has 2 divisors, whose sum is σ = 20302410. Its totient is φ = 20302408.

The previous prime is 20302397. The next prime is 20302411. The reversal of 20302409 is 90420302.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15976009 + 4326400 = 3997^2 + 2080^2 .

It is a cyclic number.

It is not a de Polignac number, because 20302409 - 2⁸ = 20302153 is a prime.

It is a super-2 number, since 2×20302409² = 824375622406562, which contains 22 as substring.

Together with 20302411, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20302459) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10151204 + 10151205.

It is an arithmetic number, because the mean of its divisors is an integer number (10151205).

Almost surely, 2^20302409 is an apocalyptic number.

It is an amenable number.

20302409 is a deficient number, since it is larger than the sum of its proper divisors (1).

20302409 is an equidigital number, since it uses as much as digits as its factorization.

20302409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 432, while the sum is 20.

The square root of 20302409 is about 4505.8194593215. The cubic root of 20302409 is about 272.8030307352.

The spelling of 20302409 in words is "twenty million, three hundred two thousand, four hundred nine".