20730031 has 4 divisors (see below), whose sum is σ = 23691472. Its totient is φ = 17768592.

The previous prime is 20730011. The next prime is 20730037. The reversal of 20730031 is 13003702.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20730031 - 2⁷ = 20729903 is a prime.

It is a super-2 number, since 2×20730031² = 859468370521922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20729987 and 20730014.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20730037) 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 3 ways as a sum of consecutive naturals, for example, 1480710 + ... + 1480723.

It is an arithmetic number, because the mean of its divisors is an integer number (5922868).

Almost surely, 2^20730031 is an apocalyptic number.

20730031 is a deficient number, since it is larger than the sum of its proper divisors (2961441).

20730031 is an equidigital number, since it uses as much as digits as its factorization.

20730031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2961440.

The product of its (nonzero) digits is 126, while the sum is 16.

The square root of 20730031 is about 4553.0243794647. The cubic root of 20730031 is about 274.7050545745.

Adding to 20730031 its reverse (13003702), we get a palindrome (33733733).

The spelling of 20730031 in words is "twenty million, seven hundred thirty thousand, thirty-one".