20342081 has 4 divisors (see below), whose sum is σ = 21538692. Its totient is φ = 19145472.

The previous prime is 20342059. The next prime is 20342083. The reversal of 20342081 is 18024302.

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

It can be written as a sum of positive squares in 2 ways, for example, as 11669056 + 8673025 = 3416^2 + 2945^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20342081 is a prime.

It is a super-2 number, since 2×20342081² = 827600518821122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20342083) 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, 598280 + ... + 598313.

It is an arithmetic number, because the mean of its divisors is an integer number (5384673).

Almost surely, 2^20342081 is an apocalyptic number.

It is an amenable number.

20342081 is a deficient number, since it is larger than the sum of its proper divisors (1196611).

20342081 is a wasteful number, since it uses less digits than its factorization.

20342081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1196610.

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 20342081 is about 4510.2196177126. The cubic root of 20342081 is about 272.9806057237.

Adding to 20342081 its reverse (18024302), we get a palindrome (38366383).

The spelling of 20342081 in words is "twenty million, three hundred forty-two thousand, eighty-one".