20421846 has 48 divisors (see below), whose sum is σ = 46962240. Its totient is φ = 6395760.

The previous prime is 20421803. The next prime is 20421859. The reversal of 20421846 is 64812402.

It is a congruent 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, 72021 + ... + 72303.

It is an arithmetic number, because the mean of its divisors is an integer number (978380).

Almost surely, 2^20421846 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20421846, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23481120).

20421846 is an abundant number, since it is smaller than the sum of its proper divisors (26540394).

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

20421846 is a wasteful number, since it uses less digits than its factorization.

20421846 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 521 (or 518 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 27.

The square root of 20421846 is about 4519.0536619961. The cubic root of 20421846 is about 273.3369425791.

The spelling of 20421846 in words is "twenty million, four hundred twenty-one thousand, eight hundred forty-six".