20438540 has 24 divisors (see below), whose sum is σ = 43512000. Its totient is φ = 8062848.

The previous prime is 20438521. The next prime is 20438567. The reversal of 20438540 is 4583402.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5540 + ... + 8459.

It is an arithmetic number, because the mean of its divisors is an integer number (1813000).

Almost surely, 2^20438540 is an apocalyptic number.

20438540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20438540 is an abundant number, since it is smaller than the sum of its proper divisors (23073460).

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

20438540 is a wasteful number, since it uses less digits than its factorization.

20438540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14081 (or 14079 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 26.

The square root of 20438540 is about 4520.9003528058. The cubic root of 20438540 is about 273.4114027774.

The spelling of 20438540 in words is "twenty million, four hundred thirty-eight thousand, five hundred forty".