20280123 has 12 divisors (see below), whose sum is σ = 29335488. Its totient is φ = 13500720.

The previous prime is 20280119. The next prime is 20280149. The reversal of 20280123 is 32108202.

It is a happy number.

It is not a de Polignac number, because 20280123 - 2² = 20280119 is a prime.

It is a super-2 number, since 2×20280123² = 822566777790258, which contains 22 as substring.

It is a hoax number, since the sum of its digits (18) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 20280096 and 20280105.

It is not an unprimeable number, because it can be changed into a prime (20280103) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8086 + ... + 10292.

It is an arithmetic number, because the mean of its divisors is an integer number (2444624).

Almost surely, 2^20280123 is an apocalyptic number.

20280123 is a deficient number, since it is larger than the sum of its proper divisors (9055365).

20280123 is a wasteful number, since it uses less digits than its factorization.

20280123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3234 (or 3231 counting only the distinct ones).

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

The square root of 20280123 is about 4503.3457562128. The cubic root of 20280123 is about 272.7031753557.

Adding to 20280123 its reverse (32108202), we get a palindrome (52388325).

The spelling of 20280123 in words is "twenty million, two hundred eighty thousand, one hundred twenty-three".