20506040 has 32 divisors (see below), whose sum is σ = 46926000. Its totient is φ = 8062464.

The previous prime is 20506037. The next prime is 20506043. The reversal of 20506040 is 4060502.

It is an interprime number because it is at equal distance from previous prime (20506037) and next prime (20506043).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20506043) 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 7 ways as a sum of consecutive naturals, for example, 1985 + ... + 6704.

Almost surely, 2^20506040 is an apocalyptic number.

20506040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20506040 is an abundant number, since it is smaller than the sum of its proper divisors (26419960).

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

20506040 is a wasteful number, since it uses less digits than its factorization.

20506040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8759 (or 8755 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 17.

The square root of 20506040 is about 4528.3595263627. The cubic root of 20506040 is about 273.7120601007.

Adding to 20506040 its reverse (4060502), we get a palindrome (24566542).

The spelling of 20506040 in words is "twenty million, five hundred six thousand, forty".