20342643 has 4 divisors (see below), whose sum is σ = 27123528. Its totient is φ = 13561760.

The previous prime is 20342633. The next prime is 20342687. The reversal of 20342643 is 34624302.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20342643 - 2⁴ = 20342627 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20342633) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3390438 + ... + 3390443.

It is an arithmetic number, because the mean of its divisors is an integer number (6780882).

Almost surely, 2^20342643 is an apocalyptic number.

20342643 is a deficient number, since it is larger than the sum of its proper divisors (6780885).

20342643 is an equidigital number, since it uses as much as digits as its factorization.

20342643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6780884.

The product of its (nonzero) digits is 3456, while the sum is 24.

The square root of 20342643 is about 4510.2819202351. The cubic root of 20342643 is about 272.9831196207.

Adding to 20342643 its reverse (34624302), we get a palindrome (54966945).

The spelling of 20342643 in words is "twenty million, three hundred forty-two thousand, six hundred forty-three".