181356373 has 6 divisors (see below), whose sum is σ = 199342262. Its totient is φ = 164869320.

The previous prime is 181356319. The next prime is 181356431. The reversal of 181356373 is 373653181.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 121727089 + 59629284 = 11033^2 + 7722^2 .

It is a de Polignac number, because none of the positive numbers 2^k-181356373 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 (181356673) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 749286 + ... + 749527.

Almost surely, 2^181356373 is an apocalyptic number.

It is an amenable number.

181356373 is a deficient number, since it is larger than the sum of its proper divisors (17985889).

181356373 is a wasteful number, since it uses less digits than its factorization.

181356373 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1498835 (or 1498824 counting only the distinct ones).

The product of its digits is 45360, while the sum is 37.

The square root of 181356373 is about 13466.8620324113. The cubic root of 181356373 is about 566.0362875094.

The spelling of 181356373 in words is "one hundred eighty-one million, three hundred fifty-six thousand, three hundred seventy-three".