1220663844 has 63 divisors (see below), whose sum is σ = 3207735307. Its totient is φ = 406259064.

The previous prime is 1220663827. The next prime is 1220663861. The reversal of 1220663844 is 4483660221.

The square root of 1220663844 is 34938.

It is a perfect power (a square), and thus also a powerful number.

1220663844 is a `hidden beast` number, since 12 + 2 + 0 + 6 + 638 + 4 + 4 = 666.

It is an interprime number because it is at equal distance from previous prime (1220663827) and next prime (1220663861).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1220663799 and 1220663808.

It is an unprimeable number.

It is a polite number, since it can be written in 20 ways as a sum of consecutive naturals, for example, 1886329 + ... + 1886975.

Almost surely, 2^1220663844 is an apocalyptic number.

1220663844 is the 34938-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1220663844

1220663844 is an abundant number, since it is smaller than the sum of its proper divisors (1987071463).

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

1220663844 is an frugal number, since it uses more digits than its factorization.

1220663844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1316 (or 652 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 36.

The cubic root of 1220663844 is about 1068.7235029442.

Multiplying 1220663844 by its sum of digits (36), we get a square (43943898384 = 209628²).

1220663844 divided by its sum of digits (36) gives a square (33907329 = 5823²).

The spelling of 1220663844 in words is "one billion, two hundred twenty million, six hundred sixty-three thousand, eight hundred forty-four".