1331556440 has 16 divisors (see below), whose sum is σ = 2996002080. Its totient is φ = 532622560.

The previous prime is 1331556439. The next prime is 1331556449. The reversal of 1331556440 is 446551331.

It is a junction number, because it is equal to n+sod(n) for n = 1331556397 and 1331556406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1331556449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16644416 + ... + 16644495.

It is an arithmetic number, because the mean of its divisors is an integer number (187250130).

Almost surely, 2^1331556440 is an apocalyptic number.

1331556440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1331556440 is an abundant number, since it is smaller than the sum of its proper divisors (1664445640).

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

1331556440 is a wasteful number, since it uses less digits than its factorization.

1331556440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33288922 (or 33288918 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 32.

The square root of 1331556440 is about 36490.4979412449. The cubic root of 1331556440 is about 1100.1532678997.

The spelling of 1331556440 in words is "one billion, three hundred thirty-one million, five hundred fifty-six thousand, four hundred forty".