20238540 has 48 divisors (see below), whose sum is σ = 64764672. Its totient is φ = 4625856.

The previous prime is 20238523. The next prime is 20238541. The reversal of 20238540 is 4583202.

It is a self number, because there is not a number n which added to its sum of digits gives 20238540.

It is not an unprimeable number, because it can be changed into a prime (20238541) 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 15 ways as a sum of consecutive naturals, for example, 23674 + ... + 24513.

It is an arithmetic number, because the mean of its divisors is an integer number (1349264).

Almost surely, 2^20238540 is an apocalyptic number.

20238540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20238540 is an abundant number, since it is smaller than the sum of its proper divisors (44526132).

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

20238540 is a wasteful number, since it uses less digits than its factorization.

20238540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48206 (or 48204 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 24.

The square root of 20238540 is about 4498.7264864626. The cubic root of 20238540 is about 272.5166614395.

The spelling of 20238540 in words is "twenty million, two hundred thirty-eight thousand, five hundred forty".