20542305 has 32 divisors (see below), whose sum is σ = 38780928. Its totient is φ = 9086400.

The previous prime is 20542283. The next prime is 20542321. The reversal of 20542305 is 50324502.

It is not a de Polignac number, because 20542305 - 2¹⁷ = 20411233 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 100 + ... + 6410.

It is an arithmetic number, because the mean of its divisors is an integer number (1211904).

Almost surely, 2^20542305 is an apocalyptic number.

It is an amenable number.

20542305 is a deficient number, since it is larger than the sum of its proper divisors (18238623).

20542305 is a wasteful number, since it uses less digits than its factorization.

20542305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6357.

The product of its (nonzero) digits is 1200, while the sum is 21.

The square root of 20542305 is about 4532.3619670101. The cubic root of 20542305 is about 273.8733186391.

Adding to 20542305 its reverse (50324502), we get a palindrome (70866807).

The spelling of 20542305 in words is "twenty million, five hundred forty-two thousand, three hundred five".