20081969 has 2 divisors, whose sum is σ = 20081970. Its totient is φ = 20081968.

The previous prime is 20081939. The next prime is 20081987. The reversal of 20081969 is 96918002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19465744 + 616225 = 4412^2 + 785^2 .

It is a cyclic number.

It is not a de Polignac number, because 20081969 - 2²⁰ = 19033393 is a prime.

It is a super-2 number, since 2×20081969² = 806570957833922, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (20081909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10040984 + 10040985.

It is an arithmetic number, because the mean of its divisors is an integer number (10040985).

Almost surely, 2^20081969 is an apocalyptic number.

It is an amenable number.

20081969 is a deficient number, since it is larger than the sum of its proper divisors (1).

20081969 is an equidigital number, since it uses as much as digits as its factorization.

20081969 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7776, while the sum is 35.

The square root of 20081969 is about 4481.2909970231. The cubic root of 20081969 is about 271.8120863629.

The spelling of 20081969 in words is "twenty million, eighty-one thousand, nine hundred sixty-nine".