20710664 has 32 divisors (see below), whose sum is σ = 42271320. Its totient is φ = 9455616.

The previous prime is 20710663. The next prime is 20710667. The reversal of 20710664 is 46601702.

It can be written as a sum of positive squares in 4 ways, for example, as 14002564 + 6708100 = 3742^2 + 2590^2 .

It is a Harshad number since it is a multiple of its sum of digits (26).

It is not an unprimeable number, because it can be changed into a prime (20710661) 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, 9062 + ... + 11114.

Almost surely, 2^20710664 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 20710664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21135660).

20710664 is an abundant number, since it is smaller than the sum of its proper divisors (21560656).

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

20710664 is a wasteful number, since it uses less digits than its factorization.

20710664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2169 (or 2165 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 26.

The square root of 20710664 is about 4550.8970544278. The cubic root of 20710664 is about 274.6194803263.

The spelling of 20710664 in words is "twenty million, seven hundred ten thousand, six hundred sixty-four".