20731073 has 16 divisors (see below), whose sum is σ = 23970816. Its totient is φ = 17743440.

The previous prime is 20731069. The next prime is 20731091. The reversal of 20731073 is 37013702.

It is not a de Polignac number, because 20731073 - 2² = 20731069 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20731043) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 16340 + ... + 17562.

It is an arithmetic number, because the mean of its divisors is an integer number (1498176).

Almost surely, 2^20731073 is an apocalyptic number.

20731073 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

20731073 is a deficient number, since it is larger than the sum of its proper divisors (3239743).

20731073 is a wasteful number, since it uses less digits than its factorization.

20731073 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1324.

The product of its (nonzero) digits is 882, while the sum is 23.

The square root of 20731073 is about 4553.1388074602. The cubic root of 20731073 is about 274.7096572026.

Adding to 20731073 its reverse (37013702), we get a palindrome (57744775).

The spelling of 20731073 in words is "twenty million, seven hundred thirty-one thousand, seventy-three".