21030680057 has 2 divisors, whose sum is σ = 21030680058. Its totient is φ = 21030680056.

The previous prime is 21030680029. The next prime is 21030680149. The reversal of 21030680057 is 75008603012.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15962806336 + 5067873721 = 126344^2 + 71189^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21030680057 is a prime.

It is not a weakly prime, because it can be changed into another prime (21030680357) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10515340028 + 10515340029.

It is an arithmetic number, because the mean of its divisors is an integer number (10515340029).

Almost surely, 2^21030680057 is an apocalyptic number.

It is an amenable number.

21030680057 is a deficient number, since it is larger than the sum of its proper divisors (1).

21030680057 is an equidigital number, since it uses as much as digits as its factorization.

21030680057 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10080, while the sum is 32.

The spelling of 21030680057 in words is "twenty-one billion, thirty million, six hundred eighty thousand, fifty-seven".