20946816 has 256 divisors, whose sum is σ = 73440000. Its totient is φ = 5806080.

The previous prime is 20946803. The next prime is 20946817. The reversal of 20946816 is 61864902.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20946817) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 722290 + ... + 722318.

It is an arithmetic number, because the mean of its divisors is an integer number (286875).

Almost surely, 2^20946816 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20946816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36720000).

20946816 is an abundant number, since it is smaller than the sum of its proper divisors (52493184).

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

20946816 is a wasteful number, since it uses less digits than its factorization.

20946816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82 (or 64 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 20946816 is about 4576.7691661258. The cubic root of 20946816 is about 275.6593149928.

The spelling of 20946816 in words is "twenty million, nine hundred forty-six thousand, eight hundred sixteen".