1666317131 has 2 divisors, whose sum is σ = 1666317132. Its totient is φ = 1666317130.

The previous prime is 1666317113. The next prime is 1666317151. The reversal of 1666317131 is 1317136661.

Together with previous prime (1666317113) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1666317131 is a prime.

It is a super-2 number, since 2×1666317131² = 5553225562128142322, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1666317091 and 1666317100.

It is not a weakly prime, because it can be changed into another prime (1666317151) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 833158565 + 833158566.

It is an arithmetic number, because the mean of its divisors is an integer number (833158566).

Almost surely, 2^1666317131 is an apocalyptic number.

1666317131 is a deficient number, since it is larger than the sum of its proper divisors (1).

1666317131 is an equidigital number, since it uses as much as digits as its factorization.

1666317131 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13608, while the sum is 35.

The square root of 1666317131 is about 40820.5479017614. The cubic root of 1666317131 is about 1185.5482116303.

The spelling of 1666317131 in words is "one billion, six hundred sixty-six million, three hundred seventeen thousand, one hundred thirty-one".