20111257 has 2 divisors, whose sum is σ = 20111258. Its totient is φ = 20111256.

The previous prime is 20111243. The next prime is 20111261. The reversal of 20111257 is 75211102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19527561 + 583696 = 4419^2 + 764^2 .

It is a cyclic number.

It is not a de Polignac number, because 20111257 - 2¹⁹ = 19586969 is a prime.

It is not a weakly prime, because it can be changed into another prime (20811257) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10055628 + 10055629.

It is an arithmetic number, because the mean of its divisors is an integer number (10055629).

Almost surely, 2^20111257 is an apocalyptic number.

It is an amenable number.

20111257 is a deficient number, since it is larger than the sum of its proper divisors (1).

20111257 is an equidigital number, since it uses as much as digits as its factorization.

20111257 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 140, while the sum is 19.

The square root of 20111257 is about 4484.5576147486. The cubic root of 20111257 is about 271.9441611515.

Adding to 20111257 its reverse (75211102), we get a palindrome (95322359).

The spelling of 20111257 in words is "twenty million, one hundred eleven thousand, two hundred fifty-seven".