20603969 has 2 divisors, whose sum is σ = 20603970. Its totient is φ = 20603968.

The previous prime is 20603941. The next prime is 20603971. The reversal of 20603969 is 96930602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20584369 + 19600 = 4537^2 + 140^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20603969 is a prime.

It is a super-2 number, since 2×20603969² = 849047077105922, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 20603971, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (20603669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10301984 + 10301985.

It is an arithmetic number, because the mean of its divisors is an integer number (10301985).

Almost surely, 2^20603969 is an apocalyptic number.

It is an amenable number.

20603969 is a deficient number, since it is larger than the sum of its proper divisors (1).

20603969 is an equidigital number, since it uses as much as digits as its factorization.

20603969 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17496, while the sum is 35.

The square root of 20603969 is about 4539.1595036967. The cubic root of 20603969 is about 274.1470830188.

The spelling of 20603969 in words is "twenty million, six hundred three thousand, nine hundred sixty-nine".