1331344657 has 2 divisors, whose sum is σ = 1331344658. Its totient is φ = 1331344656.

The previous prime is 1331344621. The next prime is 1331344733. The reversal of 1331344657 is 7564431331.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1316165841 + 15178816 = 36279^2 + 3896^2 .

It is a cyclic number.

It is not a de Polignac number, because 1331344657 - 2¹⁵ = 1331311889 is a prime.

It is not a weakly prime, because it can be changed into another prime (1331344057) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 665672328 + 665672329.

It is an arithmetic number, because the mean of its divisors is an integer number (665672329).

Almost surely, 2^1331344657 is an apocalyptic number.

It is an amenable number.

1331344657 is a deficient number, since it is larger than the sum of its proper divisors (1).

1331344657 is an equidigital number, since it uses as much as digits as its factorization.

1331344657 is an evil number, because the sum of its binary digits is even.

The product of its digits is 90720, while the sum is 37.

The square root of 1331344657 is about 36487.5959334128. The cubic root of 1331344657 is about 1100.0949386378.

Adding to 1331344657 its reverse (7564431331), we get a palindrome (8895775988).

It can be divided in two parts, 13313 and 44657, that added together give a triangular number (57970 = T₃₄₀).

The spelling of 1331344657 in words is "one billion, three hundred thirty-one million, three hundred forty-four thousand, six hundred fifty-seven".