20101011257 has 2 divisors, whose sum is σ = 20101011258. Its totient is φ = 20101011256.

The previous prime is 20101011173. The next prime is 20101011269. The reversal of 20101011257 is 75211010102.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19394461696 + 706549561 = 139264^2 + 26581^2 .

It is a cyclic number.

It is not a de Polignac number, because 20101011257 - 2³⁰ = 19027269433 is a prime.

It is not a weakly prime, because it can be changed into another prime (20101010257) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10050505628 + 10050505629.

It is an arithmetic number, because the mean of its divisors is an integer number (10050505629).

Almost surely, 2^20101011257 is an apocalyptic number.

It is an amenable number.

20101011257 is a deficient number, since it is larger than the sum of its proper divisors (1).

20101011257 is an equidigital number, since it uses as much as digits as its factorization.

20101011257 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 140, while the sum is 20.

Adding to 20101011257 its reverse (75211010102), we get a palindrome (95312021359).

The spelling of 20101011257 in words is "twenty billion, one hundred one million, eleven thousand, two hundred fifty-seven".