161391237 has 8 divisors (see below), whose sum is σ = 245929536. Its totient is φ = 92223552.

The previous prime is 161391229. The next prime is 161391257. The reversal of 161391237 is 732193161.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 161391237 - 2³ = 161391229 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 161391198 and 161391207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161391227) 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 7 ways as a sum of consecutive naturals, for example, 3842628 + ... + 3842669.

It is an arithmetic number, because the mean of its divisors is an integer number (30741192).

Almost surely, 2^161391237 is an apocalyptic number.

It is an amenable number.

161391237 is a deficient number, since it is larger than the sum of its proper divisors (84538299).

161391237 is an equidigital number, since it uses as much as digits as its factorization.

161391237 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7685307.

The product of its digits is 6804, while the sum is 33.

The square root of 161391237 is about 12703.9850834295. The cubic root of 161391237 is about 544.4524838355.

The spelling of 161391237 in words is "one hundred sixty-one million, three hundred ninety-one thousand, two hundred thirty-seven".