20257111066 has 4 divisors (see below), whose sum is σ = 30385666602. Its totient is φ = 10128555532.

The previous prime is 20257111051. The next prime is 20257111067. The reversal of 20257111066 is 66011175202.

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

It can be written as a sum of positive squares in only one way, i.e., 18476693041 + 1780418025 = 135929^2 + 42195^2 .

It is not an unprimeable number, because it can be changed into a prime (20257111067) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5064277765 + ... + 5064277768.

Almost surely, 2^20257111066 is an apocalyptic number.

20257111066 is a deficient number, since it is larger than the sum of its proper divisors (10128555536).

20257111066 is a wasteful number, since it uses less digits than its factorization.

20257111066 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10128555535.

The product of its (nonzero) digits is 5040, while the sum is 31.

Adding to 20257111066 its reverse (66011175202), we get a palindrome (86268286268).

The spelling of 20257111066 in words is "twenty billion, two hundred fifty-seven million, one hundred eleven thousand, sixty-six".