1326561556 has 6 divisors (see below), whose sum is σ = 2321482730. Its totient is φ = 663280776.

The previous prime is 1326561553. The next prime is 1326561563. The reversal of 1326561556 is 6551656231.

It can be written as a sum of positive squares in only one way, i.e., 1289959056 + 36602500 = 35916^2 + 6050^2 .

It is a super-2 number, since 2×1326561556² = 3519531123714282272, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1326561553) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 165820191 + ... + 165820198.

Almost surely, 2^1326561556 is an apocalyptic number.

It is an amenable number.

1326561556 is a deficient number, since it is larger than the sum of its proper divisors (994921174).

1326561556 is a wasteful number, since it uses less digits than its factorization.

1326561556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 331640393 (or 331640391 counting only the distinct ones).

The product of its digits is 162000, while the sum is 40.

The square root of 1326561556 is about 36421.9927516329. The cubic root of 1326561556 is about 1098.7759265178.

The spelling of 1326561556 in words is "one billion, three hundred twenty-six million, five hundred sixty-one thousand, five hundred fifty-six".