20345603 has 2 divisors, whose sum is σ = 20345604. Its totient is φ = 20345602.

The previous prime is 20345573. The next prime is 20345621. The reversal of 20345603 is 30654302.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20345603 - 2¹⁰ = 20344579 is a prime.

It is a super-2 number, since 2×20345603² = 827887122867218, which contains 22 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (20345683) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10172801 + 10172802.

It is an arithmetic number, because the mean of its divisors is an integer number (10172802).

Almost surely, 2^20345603 is an apocalyptic number.

20345603 is a deficient number, since it is larger than the sum of its proper divisors (1).

20345603 is an equidigital number, since it uses as much as digits as its factorization.

20345603 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2160, while the sum is 23.

The square root of 20345603 is about 4510.6100474326. The cubic root of 20345603 is about 272.9963593104.

Adding to 20345603 its reverse (30654302), we get a palindrome (50999905).

The spelling of 20345603 in words is "twenty million, three hundred forty-five thousand, six hundred three".