20313240 has 64 divisors (see below), whose sum is σ = 61538400. Its totient is φ = 5363712.

The previous prime is 20313229. The next prime is 20313247. The reversal of 20313240 is 4231302.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20313247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12304 + ... + 13856.

Almost surely, 2^20313240 is an apocalyptic number.

20313240 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 20313240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30769200).

20313240 is an abundant number, since it is smaller than the sum of its proper divisors (41225160).

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

20313240 is a wasteful number, since it uses less digits than its factorization.

20313240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1676 (or 1672 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 15.

The square root of 20313240 is about 4507.0211892113. The cubic root of 20313240 is about 272.8515340819.

Adding to 20313240 its reverse (4231302), we get a palindrome (24544542).

The spelling of 20313240 in words is "twenty million, three hundred thirteen thousand, two hundred forty".