161731206 has 48 divisors (see below), whose sum is σ = 431287584. Its totient is φ = 42653952.

The previous prime is 161731201. The next prime is 161731223. The reversal of 161731206 is 602137161.

161731206 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 161731206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161731201) 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 23 ways as a sum of consecutive naturals, for example, 47731 + ... + 51006.

It is an arithmetic number, because the mean of its divisors is an integer number (8985158).

Almost surely, 2^161731206 is an apocalyptic number.

161731206 is an abundant number, since it is smaller than the sum of its proper divisors (269556378).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161731206 is a wasteful number, since it uses less digits than its factorization.

161731206 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98765 (or 98762 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 27.

The square root of 161731206 is about 12717.3584521315. The cubic root of 161731206 is about 544.8345102567.

Adding to 161731206 its reverse (602137161), we get a palindrome (763868367).

It can be divided in two parts, 1617 and 31206, that added together give a palindrome (32823).

The spelling of 161731206 in words is "one hundred sixty-one million, seven hundred thirty-one thousand, two hundred six".