161838757 has 4 divisors (see below), whose sum is σ = 163657260. Its totient is φ = 160020256.

The previous prime is 161838727. The next prime is 161838769. The reversal of 161838757 is 757838161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 757838161 = 19 ⋅39886219.

It can be written as a sum of positive squares in 2 ways, for example, as 15888196 + 145950561 = 3986^2 + 12081^2 .

It is a cyclic number.

It is not a de Polignac number, because 161838757 - 2²³ = 153450149 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161838707) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 909118 + ... + 909295.

It is an arithmetic number, because the mean of its divisors is an integer number (40914315).

Almost surely, 2^161838757 is an apocalyptic number.

It is an amenable number.

161838757 is a deficient number, since it is larger than the sum of its proper divisors (1818503).

161838757 is an equidigital number, since it uses as much as digits as its factorization.

161838757 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1818502.

The product of its digits is 282240, while the sum is 46.

The square root of 161838757 is about 12721.5862611547. The cubic root of 161838757 is about 544.9552548625.

The spelling of 161838757 in words is "one hundred sixty-one million, eight hundred thirty-eight thousand, seven hundred fifty-seven".