21030385819 has 2 divisors, whose sum is σ = 21030385820. Its totient is φ = 21030385818.

The previous prime is 21030385801. The next prime is 21030385843. The reversal of 21030385819 is 91858303012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21030385819 - 2²⁷ = 20896168091 is a prime.

It is a super-2 number, since 2×21030385819² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21030385889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10515192909 + 10515192910.

It is an arithmetic number, because the mean of its divisors is an integer number (10515192910).

Almost surely, 2^21030385819 is an apocalyptic number.

21030385819 is a deficient number, since it is larger than the sum of its proper divisors (1).

21030385819 is an equidigital number, since it uses as much as digits as its factorization.

21030385819 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 51840, while the sum is 40.

The spelling of 21030385819 in words is "twenty-one billion, thirty million, three hundred eighty-five thousand, eight hundred nineteen".