665614451 has 2 divisors, whose sum is σ = 665614452. Its totient is φ = 665614450.

The previous prime is 665614387. The next prime is 665614471. The reversal of 665614451 is 154416566.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 665614451 - 2⁶ = 665614387 is a prime.

It is not a weakly prime, because it can be changed into another prime (665614471) 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 as a sum of consecutive naturals, namely, 332807225 + 332807226.

It is an arithmetic number, because the mean of its divisors is an integer number (332807226).

Almost surely, 2^665614451 is an apocalyptic number.

665614451 is a deficient number, since it is larger than the sum of its proper divisors (1).

665614451 is an equidigital number, since it uses as much as digits as its factorization.

665614451 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 86400, while the sum is 38.

The square root of 665614451 is about 25799.5048595898. The cubic root of 665614451 is about 873.1206252007.

The spelling of 665614451 in words is "six hundred sixty-five million, six hundred fourteen thousand, four hundred fifty-one".