20131730 has 8 divisors (see below), whose sum is σ = 36237132. Its totient is φ = 8052688.

The previous prime is 20131717. The next prime is 20131753. The reversal of 20131730 is 3713102.

It can be written as a sum of positive squares in 2 ways, for example, as 18003049 + 2128681 = 4243^2 + 1459^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 20131699 and 20131708.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 1006577 + ... + 1006596.

Almost surely, 2^20131730 is an apocalyptic number.

20131730 is a deficient number, since it is larger than the sum of its proper divisors (16105402).

20131730 is a wasteful number, since it uses less digits than its factorization.

20131730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2013180.

The product of its (nonzero) digits is 126, while the sum is 17.

The square root of 20131730 is about 4486.8396450063. The cubic root of 20131730 is about 272.0364084049.

Adding to 20131730 its reverse (3713102), we get a palindrome (23844832).

The spelling of 20131730 in words is "twenty million, one hundred thirty-one thousand, seven hundred thirty".