1320405556 has 12 divisors (see below), whose sum is σ = 2310964992. Its totient is φ = 660129848.

The previous prime is 1320405503. The next prime is 1320405571. The reversal of 1320405556 is 6555040231.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 56931 + ... + 76693.

It is an arithmetic number, because the mean of its divisors is an integer number (192580416).

Almost surely, 2^1320405556 is an apocalyptic number.

It is an amenable number.

1320405556 is a deficient number, since it is larger than the sum of its proper divisors (990559436).

1320405556 is a wasteful number, since it uses less digits than its factorization.

1320405556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36470 (or 36468 counting only the distinct ones).

The product of its (nonzero) digits is 18000, while the sum is 31.

The square root of 1320405556 is about 36337.3851012975. The cubic root of 1320405556 is about 1097.0736422258.

Adding to 1320405556 its reverse (6555040231), we get a palindrome (7875445787).

The spelling of 1320405556 in words is "one billion, three hundred twenty million, four hundred five thousand, five hundred fifty-six".