161229109 has 12 divisors (see below), whose sum is σ = 168290688. Its totient is φ = 154299600.

The previous prime is 161229049. The next prime is 161229121. The reversal of 161229109 is 901922161.

It is a de Polignac number, because none of the positive numbers 2^k-161229109 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161229199) 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 11 ways as a sum of consecutive naturals, for example, 764014 + ... + 764224.

It is an arithmetic number, because the mean of its divisors is an integer number (14024224).

Almost surely, 2^161229109 is an apocalyptic number.

It is an amenable number.

161229109 is a deficient number, since it is larger than the sum of its proper divisors (7061579).

161229109 is an equidigital number, since it uses as much as digits as its factorization.

161229109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 556 (or 399 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 31.

The square root of 161229109 is about 12697.6024902341. The cubic root of 161229109 is about 544.2701101031.

The spelling of 161229109 in words is "one hundred sixty-one million, two hundred twenty-nine thousand, one hundred nine".