220656639 has 8 divisors (see below), whose sum is σ = 336238720. Its totient is φ = 126089496.

The previous prime is 220656593. The next prime is 220656643. The reversal of 220656639 is 936656022.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 220656639 - 2¹² = 220652543 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 220656597 and 220656606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (220656659) 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, 5253709 + ... + 5253750.

It is an arithmetic number, because the mean of its divisors is an integer number (42029840).

Almost surely, 2^220656639 is an apocalyptic number.

220656639 is a deficient number, since it is larger than the sum of its proper divisors (115582081).

220656639 is a wasteful number, since it uses less digits than its factorization.

220656639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10507469.

The product of its (nonzero) digits is 116640, while the sum is 39.

The square root of 220656639 is about 14854.5157780387. The cubic root of 220656639 is about 604.2810839939.

The spelling of 220656639 in words is "two hundred twenty million, six hundred fifty-six thousand, six hundred thirty-nine".