1331355666 has 8 divisors (see below), whose sum is σ = 2662711344. Its totient is φ = 443785220.

The previous prime is 1331355661. The next prime is 1331355691. The reversal of 1331355666 is 6665531331.

It is a sphenic number, since it is the product of 3 distinct primes.

1331355666 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (1331355661) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 110946300 + ... + 110946311.

It is an arithmetic number, because the mean of its divisors is an integer number (332838918).

Almost surely, 2^1331355666 is an apocalyptic number.

1331355666 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

1331355666 is a wasteful number, since it uses less digits than its factorization.

1331355666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 221892616.

The product of its digits is 145800, while the sum is 39.

The square root of 1331355666 is about 36487.7467925878. The cubic root of 1331355666 is about 1100.0979708883.

Adding to 1331355666 its reverse (6665531331), we get a palindrome (7996886997).

The spelling of 1331355666 in words is "one billion, three hundred thirty-one million, three hundred fifty-five thousand, six hundred sixty-six".