20011121057 has 2 divisors, whose sum is σ = 20011121058. Its totient is φ = 20011121056.

The previous prime is 20011121017. The next prime is 20011121059. The reversal of 20011121057 is 75012111002.

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., 14440588561 + 5570532496 = 120169^2 + 74636^2 .

It is a cyclic number.

It is not a de Polignac number, because 20011121057 - 2²⁸ = 19742685601 is a prime.

Together with 20011121059, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20011121059) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10005560528 + 10005560529.

It is an arithmetic number, because the mean of its divisors is an integer number (10005560529).

Almost surely, 2^20011121057 is an apocalyptic number.

It is an amenable number.

20011121057 is a deficient number, since it is larger than the sum of its proper divisors (1).

20011121057 is an equidigital number, since it uses as much as digits as its factorization.

20011121057 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 20.

Adding to 20011121057 its reverse (75012111002), we get a palindrome (95023232059).

The spelling of 20011121057 in words is "twenty billion, eleven million, one hundred twenty-one thousand, fifty-seven".