20803057 has 4 divisors (see below), whose sum is σ = 22694256. Its totient is φ = 18911860.

The previous prime is 20803021. The next prime is 20803061. The reversal of 20803057 is 75030802.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 20803057 - 2¹⁵ = 20770289 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20803007) 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, 945583 + ... + 945604.

It is an arithmetic number, because the mean of its divisors is an integer number (5673564).

Almost surely, 2^20803057 is an apocalyptic number.

It is an amenable number.

20803057 is a deficient number, since it is larger than the sum of its proper divisors (1891199).

20803057 is a wasteful number, since it uses less digits than its factorization.

20803057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1891198.

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 20803057 is about 4561.0368338789. The cubic root of 20803057 is about 275.0272457854.

Adding to 20803057 its reverse (75030802), we get a palindrome (95833859).

The spelling of 20803057 in words is "twenty million, eight hundred three thousand, fifty-seven".