20321240 has 32 divisors (see below), whose sum is σ = 46841760. Its totient is φ = 7929600.

The previous prime is 20321237. The next prime is 20321243. The reversal of 20321240 is 4212302.

It is an interprime number because it is at equal distance from previous prime (20321237) and next prime (20321243).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20321243) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4556 + ... + 7835.

It is an arithmetic number, because the mean of its divisors is an integer number (1463805).

Almost surely, 2^20321240 is an apocalyptic number.

20321240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20321240 is an abundant number, since it is smaller than the sum of its proper divisors (26520520).

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

20321240 is a wasteful number, since it uses less digits than its factorization.

20321240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12443 (or 12439 counting only the distinct ones).

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

The square root of 20321240 is about 4507.9086059946. The cubic root of 20321240 is about 272.8873485848.

Adding to 20321240 its reverse (4212302), we get a palindrome (24533542).

The spelling of 20321240 in words is "twenty million, three hundred twenty-one thousand, two hundred forty".