161238091 has 8 divisors (see below), whose sum is σ = 187395840. Its totient is φ = 135861288.

The previous prime is 161238071. The next prime is 161238101. The reversal of 161238091 is 190832161.

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

It is a cyclic number.

It is not a de Polignac number, because 161238091 - 2⁷ = 161237963 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161238001) 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, 194791 + ... + 195616.

It is an arithmetic number, because the mean of its divisors is an integer number (23424480).

Almost surely, 2^161238091 is an apocalyptic number.

161238091 is a deficient number, since it is larger than the sum of its proper divisors (26157749).

161238091 is an equidigital number, since it uses as much as digits as its factorization.

161238091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 390473.

The product of its (nonzero) digits is 2592, while the sum is 31.

The square root of 161238091 is about 12697.9561741250. The cubic root of 161238091 is about 544.2802169285.

The spelling of 161238091 in words is "one hundred sixty-one million, two hundred thirty-eight thousand, ninety-one".