20658040 has 32 divisors (see below), whose sum is σ = 50057280. Its totient is φ = 7627392.

The previous prime is 20658037. The next prime is 20658047. The reversal of 20658040 is 4085602.

It is a junction number, because it is equal to n+sod(n) for n = 20657996 and 20658014.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20658047) 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, 19344 + ... + 20383.

It is an arithmetic number, because the mean of its divisors is an integer number (1564290).

Almost surely, 2^20658040 is an apocalyptic number.

20658040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20658040 is an abundant number, since it is smaller than the sum of its proper divisors (29399240).

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

20658040 is a wasteful number, since it uses less digits than its factorization.

20658040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39751 (or 39747 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 20658040 is about 4545.1116597945. Note that the first 3 decimals coincide. The cubic root of 20658040 is about 274.3866882905.

The spelling of 20658040 in words is "twenty million, six hundred fifty-eight thousand, forty".