1331783997 has 4 divisors (see below), whose sum is σ = 1775712000. Its totient is φ = 887855996.

The previous prime is 1331783989. The next prime is 1331784001. The reversal of 1331783997 is 7993871331.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1331783997 - 2³ = 1331783989 is a prime.

It is a super-2 number, since 2×1331783997² = 3547297229330592018, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1331783977) 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, 221963997 + ... + 221964002.

It is an arithmetic number, because the mean of its divisors is an integer number (443928000).

Almost surely, 2^1331783997 is an apocalyptic number.

It is an amenable number.

1331783997 is a deficient number, since it is larger than the sum of its proper divisors (443928003).

1331783997 is an equidigital number, since it uses as much as digits as its factorization.

1331783997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 443928002.

The product of its digits is 857304, while the sum is 51.

The square root of 1331783997 is about 36493.6158389382. The cubic root of 1331783997 is about 1100.2159347433.

The spelling of 1331783997 in words is "one billion, three hundred thirty-one million, seven hundred eighty-three thousand, nine hundred ninety-seven".