20123240 has 64 divisors (see below), whose sum is σ = 48580560. Its totient is φ = 7475200.

The previous prime is 20123239. The next prime is 20123263. The reversal of 20123240 is 4232102.

It can be written as a sum of positive squares in 8 ways, for example, as 19731364 + 391876 = 4442^2 + 626^2 .

It is an unprimeable number.

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, 68534 + ... + 68826.

Almost surely, 2^20123240 is an apocalyptic number.

20123240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20123240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24290280).

20123240 is an abundant number, since it is smaller than the sum of its proper divisors (28457320).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20123240 is a wasteful number, since it uses less digits than its factorization.

20123240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 422 (or 418 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 14.

The square root of 20123240 is about 4485.8934450118. The cubic root of 20123240 is about 271.9981617523.

Adding to 20123240 its reverse (4232102), we get a palindrome (24355342).

The spelling of 20123240 in words is "twenty million, one hundred twenty-three thousand, two hundred forty".