20351223 has 16 divisors (see below), whose sum is σ = 31737600. Its totient is φ = 12853080.

The previous prime is 20351207. The next prime is 20351239. The reversal of 20351223 is 32215302.

It is an interprime number because it is at equal distance from previous prime (20351207) and next prime (20351239).

It is not a de Polignac number, because 20351223 - 2⁴ = 20351207 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20351196 and 20351205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20351263) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19323 + ... + 20348.

It is an arithmetic number, because the mean of its divisors is an integer number (1983600).

Almost surely, 2^20351223 is an apocalyptic number.

20351223 is a deficient number, since it is larger than the sum of its proper divisors (11386377).

20351223 is a wasteful number, since it uses less digits than its factorization.

20351223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39699 (or 39693 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 18.

The square root of 20351223 is about 4511.2329800178. The cubic root of 20351223 is about 273.0214932963.

Adding to 20351223 its reverse (32215302), we get a palindrome (52566525).

The spelling of 20351223 in words is "twenty million, three hundred fifty-one thousand, two hundred twenty-three".