20840346 has 48 divisors (see below), whose sum is σ = 47848320. Its totient is φ = 6541920.

The previous prime is 20840311. The next prime is 20840363. The reversal of 20840346 is 64304802.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 29040 + ... + 29748.

It is an arithmetic number, because the mean of its divisors is an integer number (996840).

Almost surely, 2^20840346 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20840346, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23924160).

20840346 is an abundant number, since it is smaller than the sum of its proper divisors (27007974).

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

20840346 is a wasteful number, since it uses less digits than its factorization.

20840346 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 811 (or 808 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 27.

The square root of 20840346 is about 4565.1227803861. The cubic root of 20840346 is about 275.1914743646.

The spelling of 20840346 in words is "twenty million, eight hundred forty thousand, three hundred forty-six".