161222212 has 6 divisors (see below), whose sum is σ = 282138878. Its totient is φ = 80611104.

The previous prime is 161222197. The next prime is 161222213. The reversal of 161222212 is 212222161.

It can be written as a sum of positive squares in only one way, i.e., 159415876 + 1806336 = 12626^2 + 1344^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 161222212.

It is not an unprimeable number, because it can be changed into a prime (161222213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20152773 + ... + 20152780.

Almost surely, 2^161222212 is an apocalyptic number.

It is an amenable number.

161222212 is a deficient number, since it is larger than the sum of its proper divisors (120916666).

161222212 is a wasteful number, since it uses less digits than its factorization.

161222212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40305557 (or 40305555 counting only the distinct ones).

The product of its digits is 192, while the sum is 19.

The square root of 161222212 is about 12697.3309006263. The cubic root of 161222212 is about 544.2623491297.

Adding to 161222212 its reverse (212222161), we get a palindrome (373444373).

The spelling of 161222212 in words is "one hundred sixty-one million, two hundred twenty-two thousand, two hundred twelve".