161222513 has 8 divisors (see below), whose sum is σ = 167265000. Its totient is φ = 155212288.

The previous prime is 161222497. The next prime is 161222519. The reversal of 161222513 is 315222161.

161222513 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 237169 + 160985344 = 487^2 + 12688^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 161222513 - 2⁴ = 161222497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161222519) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2363 + ... + 18111.

It is an arithmetic number, because the mean of its divisors is an integer number (20908125).

Almost surely, 2^161222513 is an apocalyptic number.

It is an amenable number.

161222513 is a deficient number, since it is larger than the sum of its proper divisors (6042487).

161222513 is a wasteful number, since it uses less digits than its factorization.

161222513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16131.

The product of its digits is 720, while the sum is 23.

The square root of 161222513 is about 12697.3427535056. The cubic root of 161222513 is about 544.2626878400.

Adding to 161222513 its reverse (315222161), we get a palindrome (476444674).

The spelling of 161222513 in words is "one hundred sixty-one million, two hundred twenty-two thousand, five hundred thirteen".