20647776 has 48 divisors (see below), whose sum is σ = 55674864. Its totient is φ = 6695424.

The previous prime is 20647769. The next prime is 20647777. The reversal of 20647776 is 67774602.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20647777) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 646 + ... + 6458.

It is an arithmetic number, because the mean of its divisors is an integer number (1159893).

Almost surely, 2^20647776 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 20647776, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27837432).

20647776 is an abundant number, since it is smaller than the sum of its proper divisors (35027088).

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

20647776 is a wasteful number, since it uses less digits than its factorization.

20647776 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5863 (or 5855 counting only the distinct ones).

The product of its (nonzero) digits is 98784, while the sum is 39.

The square root of 20647776 is about 4543.9823943321. The cubic root of 20647776 is about 274.3412375197.

The spelling of 20647776 in words is "twenty million, six hundred forty-seven thousand, seven hundred seventy-six".