20660778 has 32 divisors (see below), whose sum is σ = 46785600. Its totient is φ = 6756048.

The previous prime is 20660767. The next prime is 20660779. The reversal of 20660778 is 87706602.

It is not an unprimeable number, because it can be changed into a prime (20660779) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 748 + ... + 6471.

It is an arithmetic number, because the mean of its divisors is an integer number (1462050).

Almost surely, 2^20660778 is an apocalyptic number.

20660778 is an abundant number, since it is smaller than the sum of its proper divisors (26124822).

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

20660778 is a wasteful number, since it uses less digits than its factorization.

20660778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7283 (or 7277 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 36.

The square root of 20660778 is about 4545.4128525361. The cubic root of 20660778 is about 274.3988100853.

The spelling of 20660778 in words is "twenty million, six hundred sixty thousand, seven hundred seventy-eight".