161223789 has 16 divisors (see below), whose sum is σ = 223761600. Its totient is φ = 103130496.

The previous prime is 161223787. The next prime is 161223791. The reversal of 161223789 is 987322161.

It is an interprime number because it is at equal distance from previous prime (161223787) and next prime (161223791).

It is not a de Polignac number, because 161223789 - 2¹ = 161223787 is a prime.

It is a super-2 number, since 2×161223789² = 51986220279033042, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161223787) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8497 + ... + 19865.

It is an arithmetic number, because the mean of its divisors is an integer number (13985100).

Almost surely, 2^161223789 is an apocalyptic number.

It is an amenable number.

161223789 is a deficient number, since it is larger than the sum of its proper divisors (62537811).

161223789 is a wasteful number, since it uses less digits than its factorization.

161223789 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11564.

The product of its digits is 36288, while the sum is 39.

The square root of 161223789 is about 12697.3930001398. The cubic root of 161223789 is about 544.2641236969.

The spelling of 161223789 in words is "one hundred sixty-one million, two hundred twenty-three thousand, seven hundred eighty-nine".