2161501604123 has 2 divisors, whose sum is σ = 2161501604124. Its totient is φ = 2161501604122.

The previous prime is 2161501604069. The next prime is 2161501604149. The reversal of 2161501604123 is 3214061051612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2161501604123 - 2⁸ = 2161501603867 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2161501604123.

It is not a weakly prime, because it can be changed into another prime (2161501604173) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1080750802061 + 1080750802062.

It is an arithmetic number, because the mean of its divisors is an integer number (1080750802062).

Almost surely, 2^{2161501604123} is an apocalyptic number.

2161501604123 is a deficient number, since it is larger than the sum of its proper divisors (1).

2161501604123 is an equidigital number, since it uses as much as digits as its factorization.

2161501604123 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8640, while the sum is 32.

Adding to 2161501604123 its reverse (3214061051612), we get a palindrome (5375562655735).

The spelling of 2161501604123 in words is "two trillion, one hundred sixty-one billion, five hundred one million, six hundred four thousand, one hundred twenty-three".