20770656 has 72 divisors (see below), whose sum is σ = 57135960. Its totient is φ = 6606336.

The previous prime is 20770637. The next prime is 20770657. The reversal of 20770656 is 65607702.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20770657) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 50580 + ... + 50988.

It is an arithmetic number, because the mean of its divisors is an integer number (793555).

Almost surely, 2^20770656 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 20770656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28567980).

20770656 is an abundant number, since it is smaller than the sum of its proper divisors (36365304).

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

20770656 is a wasteful number, since it uses less digits than its factorization.

20770656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 468 (or 437 counting only the distinct ones).

The product of its (nonzero) digits is 17640, while the sum is 33.

The square root of 20770656 is about 4557.4835161523. The cubic root of 20770656 is about 274.8843855604.

The spelling of 20770656 in words is "twenty million, seven hundred seventy thousand, six hundred fifty-six".