199425658021 has 2 divisors, whose sum is σ = 199425658022. Its totient is φ = 199425658020.

The previous prime is 199425658001. The next prime is 199425658049. The reversal of 199425658021 is 120856524991.

It is a happy number.

199425658021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 168551302500 + 30874355521 = 410550^2 + 175711^2 .

It is a cyclic number.

It is not a de Polignac number, because 199425658021 - 2³⁵ = 165065919653 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 199425658021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199425658001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99712829010 + 99712829011.

It is an arithmetic number, because the mean of its divisors is an integer number (99712829011).

Almost surely, 2^199425658021 is an apocalyptic number.

It is an amenable number.

199425658021 is a deficient number, since it is larger than the sum of its proper divisors (1).

199425658021 is an equidigital number, since it uses as much as digits as its factorization.

199425658021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1555200, while the sum is 52.

The spelling of 199425658021 in words is "one hundred ninety-nine billion, four hundred twenty-five million, six hundred fifty-eight thousand, twenty-one".