20355240 has 32 divisors (see below), whose sum is σ = 61066080. Its totient is φ = 5428032.

The previous prime is 20355221. The next prime is 20355241. The reversal of 20355240 is 4255302.

It is not an unprimeable number, because it can be changed into a prime (20355241) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 84694 + ... + 84933.

It is an arithmetic number, because the mean of its divisors is an integer number (1908315).

Almost surely, 2^20355240 is an apocalyptic number.

20355240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20355240 is an abundant number, since it is smaller than the sum of its proper divisors (40710840).

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

20355240 is a wasteful number, since it uses less digits than its factorization.

20355240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 169641 (or 169637 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 21.

The square root of 20355240 is about 4511.6781800124. The cubic root of 20355240 is about 273.0394554468.

The spelling of 20355240 in words is "twenty million, three hundred fifty-five thousand, two hundred forty".