20446840 has 16 divisors (see below), whose sum is σ = 46005480. Its totient is φ = 8178720.

The previous prime is 20446837. The next prime is 20446843. The reversal of 20446840 is 4864402.

It is an interprime number because it is at equal distance from previous prime (20446837) and next prime (20446843).

It is a junction number, because it is equal to n+sod(n) for n = 20446799 and 20446808.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20446843) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 255546 + ... + 255625.

Almost surely, 2^20446840 is an apocalyptic number.

20446840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20446840 is an abundant number, since it is smaller than the sum of its proper divisors (25558640).

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

20446840 is a wasteful number, since it uses less digits than its factorization.

20446840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 511182 (or 511178 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 28.

The square root of 20446840 is about 4521.8182183719. The cubic root of 20446840 is about 273.4484081526.

The spelling of 20446840 in words is "twenty million, four hundred forty-six thousand, eight hundred forty".