20111057 has 4 divisors (see below), whose sum is σ = 20578800. Its totient is φ = 19643316.

The previous prime is 20111053. The next prime is 20111071. The reversal of 20111057 is 75011102.

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 a cyclic number.

It is not a de Polignac number, because 20111057 - 2² = 20111053 is a prime.

It is a super-2 number, since 2×20111057² = 808909227314498, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20111053) 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, 233807 + ... + 233892.

It is an arithmetic number, because the mean of its divisors is an integer number (5144700).

Almost surely, 2^20111057 is an apocalyptic number.

It is an amenable number.

20111057 is a deficient number, since it is larger than the sum of its proper divisors (467743).

20111057 is an equidigital number, since it uses as much as digits as its factorization.

20111057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 467742.

The product of its (nonzero) digits is 70, while the sum is 17.

The square root of 20111057 is about 4484.5353159497. The cubic root of 20111057 is about 271.9432596827.

Adding to 20111057 its reverse (75011102), we get a palindrome (95122159).

The spelling of 20111057 in words is "twenty million, one hundred eleven thousand, fifty-seven".