20281023 has 24 divisors (see below), whose sum is σ = 34722688. Its totient is φ = 11588184.

The previous prime is 20281013. The next prime is 20281039. The reversal of 20281023 is 32018202.

It is a happy number.

It is not a de Polignac number, because 20281023 - 2⁴ = 20281007 is a prime.

It is a super-2 number, since 2×20281023² = 822639787853058, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20280987 and 20281005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20281003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4261 + ... + 7662.

Almost surely, 2^20281023 is an apocalyptic number.

20281023 is a deficient number, since it is larger than the sum of its proper divisors (14441665).

20281023 is an equidigital number, since it uses as much as digits as its factorization.

20281023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11945 (or 11933 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 20281023 is about 4503.4456808093. The cubic root of 20281023 is about 272.7072093422.

Adding to 20281023 its reverse (32018202), we get a palindrome (52299225).

It can be divided in two parts, 202 and 81023, that added together give a square (81225 = 285²).

The spelling of 20281023 in words is "twenty million, two hundred eighty-one thousand, twenty-three".