20731223 has 8 divisors (see below), whose sum is σ = 21936000. Its totient is φ = 19537848.

The previous prime is 20731189. The next prime is 20731231. The reversal of 20731223 is 32213702.

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

It is a cyclic number.

It is not a de Polignac number, because 20731223 - 2¹⁸ = 20469079 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20731195 and 20731204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20731253) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1040 + ... + 6522.

It is an arithmetic number, because the mean of its divisors is an integer number (2742000).

Almost surely, 2^20731223 is an apocalyptic number.

20731223 is a deficient number, since it is larger than the sum of its proper divisors (1204777).

20731223 is a wasteful number, since it uses less digits than its factorization.

20731223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5701.

The product of its (nonzero) digits is 504, while the sum is 20.

The square root of 20731223 is about 4553.1552795836. The cubic root of 20731223 is about 274.7103197564.

Adding to 20731223 its reverse (32213702), we get a palindrome (52944925).

The spelling of 20731223 in words is "twenty million, seven hundred thirty-one thousand, two hundred twenty-three".