161686437 has 16 divisors (see below), whose sum is σ = 235421760. Its totient is φ = 97891200.

The previous prime is 161686391. The next prime is 161686451. The reversal of 161686437 is 734686161.

It is not a de Polignac number, because 161686437 - 2¹¹ = 161684389 is a prime.

It is a super-2 number, since 2×161686437² = 52285007819509938, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161686237) 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, 41739 + ... + 45447.

It is an arithmetic number, because the mean of its divisors is an integer number (14713860).

Almost surely, 2^161686437 is an apocalyptic number.

It is an amenable number.

161686437 is a deficient number, since it is larger than the sum of its proper divisors (73735323).

161686437 is a wasteful number, since it uses less digits than its factorization.

161686437 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5044.

The product of its digits is 145152, while the sum is 42.

The square root of 161686437 is about 12715.5981770422. The cubic root of 161686437 is about 544.7842335295.

The spelling of 161686437 in words is "one hundred sixty-one million, six hundred eighty-six thousand, four hundred thirty-seven".