20408730 has 16 divisors (see below), whose sum is σ = 48981024. Its totient is φ = 5442320.

The previous prime is 20408711. The next prime is 20408743. The reversal of 20408730 is 3780402.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20408730.

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, 340116 + ... + 340175.

It is an arithmetic number, because the mean of its divisors is an integer number (3061314).

Almost surely, 2^20408730 is an apocalyptic number.

20408730 is an abundant number, since it is smaller than the sum of its proper divisors (28572294).

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

20408730 is a wasteful number, since it uses less digits than its factorization.

20408730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 680301.

The product of its (nonzero) digits is 1344, while the sum is 24.

The square root of 20408730 is about 4517.6022401269. The cubic root of 20408730 is about 273.2784128535.

The spelling of 20408730 in words is "twenty million, four hundred eight thousand, seven hundred thirty".