20842057 has 8 divisors (see below), whose sum is σ = 21542400. Its totient is φ = 20151600.

The previous prime is 20842049. The next prime is 20842093. The reversal of 20842057 is 75024802.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20842057 - 2³ = 20842049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20842007) 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 7 ways as a sum of consecutive naturals, for example, 1944 + ... + 6742.

It is an arithmetic number, because the mean of its divisors is an integer number (2692800).

Almost surely, 2^20842057 is an apocalyptic number.

It is an amenable number.

20842057 is a deficient number, since it is larger than the sum of its proper divisors (700343).

20842057 is a wasteful number, since it uses less digits than its factorization.

20842057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4943.

The product of its (nonzero) digits is 4480, while the sum is 28.

The square root of 20842057 is about 4565.3101756617. The cubic root of 20842057 is about 275.1990052653.

Adding to 20842057 its reverse (75024802), we get a palindrome (95866859).

The spelling of 20842057 in words is "twenty million, eight hundred forty-two thousand, fifty-seven".