1308001990021 has 2 divisors, whose sum is σ = 1308001990022. Its totient is φ = 1308001990020.

The previous prime is 1308001989989. The next prime is 1308001990049. The reversal of 1308001990021 is 1200991008031.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1273139872225 + 34862117796 = 1128335^2 + 186714^2 .

It is a cyclic number.

It is not a de Polignac number, because 1308001990021 - 2⁵ = 1308001989989 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1308001390021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 654000995010 + 654000995011.

It is an arithmetic number, because the mean of its divisors is an integer number (654000995011).

Almost surely, 2^{1308001990021} is an apocalyptic number.

It is an amenable number.

1308001990021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1308001990021 is an equidigital number, since it uses as much as digits as its factorization.

1308001990021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3888, while the sum is 34.

Adding to 1308001990021 its reverse (1200991008031), we get a palindrome (2508992998052).

The spelling of 1308001990021 in words is "one trillion, three hundred eight billion, one million, nine hundred ninety thousand, twenty-one".