161102521 has 2 divisors, whose sum is σ = 161102522. Its totient is φ = 161102520.

The previous prime is 161102519. The next prime is 161102527. The reversal of 161102521 is 125201161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 157628025 + 3474496 = 12555^2 + 1864^2 .

It is a cyclic number.

It is not a de Polignac number, because 161102521 - 2¹ = 161102519 is a prime.

Together with 161102519, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (161102527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80551260 + 80551261.

It is an arithmetic number, because the mean of its divisors is an integer number (80551261).

Almost surely, 2^161102521 is an apocalyptic number.

It is an amenable number.

161102521 is a deficient number, since it is larger than the sum of its proper divisors (1).

161102521 is an equidigital number, since it uses as much as digits as its factorization.

161102521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 120, while the sum is 19.

The square root of 161102521 is about 12692.6167908749. The cubic root of 161102521 is about 544.1276294129.

Adding to 161102521 its reverse (125201161), we get a palindrome (286303682).

The spelling of 161102521 in words is "one hundred sixty-one million, one hundred two thousand, five hundred twenty-one".