20766456 has 80 divisors (see below), whose sum is σ = 59096400. Its totient is φ = 6811776.

The previous prime is 20766451. The next prime is 20766467. The reversal of 20766456 is 65466702.

20766456 is a `hidden beast` number, since 2 + 0 + 7 + 6 + 645 + 6 = 666.

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

It is a self number, because there is not a number n which added to its sum of digits gives 20766456.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20766451) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 47085 + ... + 47523.

It is an arithmetic number, because the mean of its divisors is an integer number (738705).

Almost surely, 2^20766456 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 20766456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29548200).

20766456 is an abundant number, since it is smaller than the sum of its proper divisors (38329944).

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

20766456 is a wasteful number, since it uses less digits than its factorization.

20766456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 530 (or 517 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 36.

The square root of 20766456 is about 4557.0227122541. The cubic root of 20766456 is about 274.8658563391.

The spelling of 20766456 in words is "twenty million, seven hundred sixty-six thousand, four hundred fifty-six".