20643043 has 2 divisors, whose sum is σ = 20643044. Its totient is φ = 20643042.

The previous prime is 20642971. The next prime is 20643061. The reversal of 20643043 is 34034602.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20643043 - 2¹³ = 20634851 is a prime.

It is a super-2 number, since 2×20643043² = 852270448599698, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20643143) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10321521 + 10321522.

It is an arithmetic number, because the mean of its divisors is an integer number (10321522).

Almost surely, 2^20643043 is an apocalyptic number.

20643043 is a deficient number, since it is larger than the sum of its proper divisors (1).

20643043 is an equidigital number, since it uses as much as digits as its factorization.

20643043 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1728, while the sum is 22.

The square root of 20643043 is about 4543.4615658108. The cubic root of 20643043 is about 274.3202739011.

Adding to 20643043 its reverse (34034602), we get a palindrome (54677645).

The spelling of 20643043 in words is "twenty million, six hundred forty-three thousand, forty-three".