199505146021 has 2 divisors, whose sum is σ = 199505146022. Its totient is φ = 199505146020.

The previous prime is 199505145937. The next prime is 199505146039. The reversal of 199505146021 is 120641505991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 137556424996 + 61948721025 = 370886^2 + 248895^2 .

It is a cyclic number.

It is not a de Polignac number, because 199505146021 - 2¹⁵ = 199505113253 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199505146091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99752573010 + 99752573011.

It is an arithmetic number, because the mean of its divisors is an integer number (99752573011).

Almost surely, 2^199505146021 is an apocalyptic number.

It is an amenable number.

199505146021 is a deficient number, since it is larger than the sum of its proper divisors (1).

199505146021 is an equidigital number, since it uses as much as digits as its factorization.

199505146021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 97200, while the sum is 43.

The spelling of 199505146021 in words is "one hundred ninety-nine billion, five hundred five million, one hundred forty-six thousand, twenty-one".