1331039865 has 16 divisors (see below), whose sum is σ = 2131823808. Its totient is φ = 709167936.

The previous prime is 1331039863. The next prime is 1331039893. The reversal of 1331039865 is 5689301331.

It is not a de Polignac number, because 1331039865 - 2¹ = 1331039863 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1331039861) 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 15 ways as a sum of consecutive naturals, for example, 29547 + ... + 59456.

It is an arithmetic number, because the mean of its divisors is an integer number (133238988).

Almost surely, 2^1331039865 is an apocalyptic number.

1331039865 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1331039865 is a deficient number, since it is larger than the sum of its proper divisors (800783943).

1331039865 is an equidigital number, since it uses as much as digits as its factorization.

1331039865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90008.

The product of its (nonzero) digits is 58320, while the sum is 39.

The square root of 1331039865 is about 36483.4190420799. The cubic root of 1331039865 is about 1100.0109819840.

The spelling of 1331039865 in words is "one billion, three hundred thirty-one million, thirty-nine thousand, eight hundred sixty-five".