1666426319 has 2 divisors, whose sum is σ = 1666426320. Its totient is φ = 1666426318.

The previous prime is 1666426277. The next prime is 1666426327. The reversal of 1666426319 is 9136246661.

It is a strong prime.

It is an emirp because it is prime and its reverse (9136246661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1666426319 - 2⁸ = 1666426063 is a prime.

It is a super-2 number, since 2×1666426319² = 5553953353311779522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1666426319.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1666426339) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 833213159 + 833213160.

It is an arithmetic number, because the mean of its divisors is an integer number (833213160).

Almost surely, 2^1666426319 is an apocalyptic number.

1666426319 is a deficient number, since it is larger than the sum of its proper divisors (1).

1666426319 is an equidigital number, since it uses as much as digits as its factorization.

1666426319 is an evil number, because the sum of its binary digits is even.

The product of its digits is 279936, while the sum is 44.

The square root of 1666426319 is about 40821.8852945329. The cubic root of 1666426319 is about 1185.5741060231.

The spelling of 1666426319 in words is "one billion, six hundred sixty-six million, four hundred twenty-six thousand, three hundred nineteen".