201321870161 has 2 divisors, whose sum is σ = 201321870162. Its totient is φ = 201321870160.

The previous prime is 201321870083. The next prime is 201321870179. The reversal of 201321870161 is 161078123102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 175426945600 + 25894924561 = 418840^2 + 160919^2 .

It is a cyclic number.

It is not a de Polignac number, because 201321870161 - 2¹⁰ = 201321869137 is a prime.

It is not a weakly prime, because it can be changed into another prime (201321870181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100660935080 + 100660935081.

It is an arithmetic number, because the mean of its divisors is an integer number (100660935081).

Almost surely, 2^201321870161 is an apocalyptic number.

It is an amenable number.

201321870161 is a deficient number, since it is larger than the sum of its proper divisors (1).

201321870161 is an equidigital number, since it uses as much as digits as its factorization.

201321870161 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4032, while the sum is 32.

Adding to 201321870161 its reverse (161078123102), we get a palindrome (362399993263).

The spelling of 201321870161 in words is "two hundred one billion, three hundred twenty-one million, eight hundred seventy thousand, one hundred sixty-one".