21020210020057 has 2 divisors, whose sum is σ = 21020210020058. Its totient is φ = 21020210020056.

The previous prime is 21020210019971. The next prime is 21020210020063. The reversal of 21020210020057 is 75002001202012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12992485131081 + 8027724888976 = 3604509^2 + 2833324^2 .

It is a cyclic number.

It is not a de Polignac number, because 21020210020057 - 2¹¹ = 21020210018009 is a prime.

It is not a weakly prime, because it can be changed into another prime (21020210020067) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510105010028 + 10510105010029.

It is an arithmetic number, because the mean of its divisors is an integer number (10510105010029).

Almost surely, 2^{21020210020057} is an apocalyptic number.

It is an amenable number.

21020210020057 is a deficient number, since it is larger than the sum of its proper divisors (1).

21020210020057 is an equidigital number, since it uses as much as digits as its factorization.

21020210020057 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 560, while the sum is 22.

Adding to 21020210020057 its reverse (75002001202012), we get a palindrome (96022211222069).

The spelling of 21020210020057 in words is "twenty-one trillion, twenty billion, two hundred ten million, twenty thousand, fifty-seven".