1666314997 has 2 divisors, whose sum is σ = 1666314998. Its totient is φ = 1666314996.

The previous prime is 1666314983. The next prime is 1666315039. The reversal of 1666314997 is 7994136661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 954439236 + 711875761 = 30894^2 + 26681^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1666314997 is a prime.

It is a super-2 number, since 2×1666314997² = 5553211338454220018, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1666314917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 833157498 + 833157499.

It is an arithmetic number, because the mean of its divisors is an integer number (833157499).

Almost surely, 2^1666314997 is an apocalyptic number.

It is an amenable number.

1666314997 is a deficient number, since it is larger than the sum of its proper divisors (1).

1666314997 is an equidigital number, since it uses as much as digits as its factorization.

1666314997 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1469664, while the sum is 52.

The square root of 1666314997 is about 40820.5217629564. The cubic root of 1666314997 is about 1185.5477055320.

The spelling of 1666314997 in words is "one billion, six hundred sixty-six million, three hundred fourteen thousand, nine hundred ninety-seven".