18131402 has 8 divisors (see below), whose sum is σ = 27396036. Its totient is φ = 8999392.

The previous prime is 18131381. The next prime is 18131411. The reversal of 18131402 is 20413181.

It can be written as a sum of positive squares in 2 ways, for example, as 17230801 + 900601 = 4151^2 + 949^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32813 + ... + 33360.

Almost surely, 2^18131402 is an apocalyptic number.

18131402 is a deficient number, since it is larger than the sum of its proper divisors (9264634).

18131402 is a wasteful number, since it uses less digits than its factorization.

18131402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66312.

The product of its (nonzero) digits is 192, while the sum is 20.

The square root of 18131402 is about 4258.0984018691. The cubic root of 18131402 is about 262.7103173124.

Adding to 18131402 its reverse (20413181), we get a palindrome (38544583).

The spelling of 18131402 in words is "eighteen million, one hundred thirty-one thousand, four hundred two".