20742343 has 4 divisors (see below), whose sum is σ = 21644208. Its totient is φ = 19840480.

The previous prime is 20742307. The next prime is 20742353. The reversal of 20742343 is 34324702.

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 20742343 - 2²¹ = 18645191 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20742353) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 450898 + ... + 450943.

It is an arithmetic number, because the mean of its divisors is an integer number (5411052).

Almost surely, 2^20742343 is an apocalyptic number.

20742343 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

20742343 is a deficient number, since it is larger than the sum of its proper divisors (901865).

20742343 is an equidigital number, since it uses as much as digits as its factorization.

20742343 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 901864.

The product of its (nonzero) digits is 4032, while the sum is 25.

The square root of 20742343 is about 4554.3762470837. The cubic root of 20742343 is about 274.7594281750.

The spelling of 20742343 in words is "twenty million, seven hundred forty-two thousand, three hundred forty-three".