666403397 has 16 divisors (see below), whose sum is σ = 779699520. Its totient is φ = 563097600.

The previous prime is 666403351. The next prime is 666403421. The reversal of 666403397 is 793304666.

It is a cyclic number.

It is not a de Polignac number, because 666403397 - 2⁶ = 666403333 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666403097) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19004 + ... + 41157.

It is an arithmetic number, because the mean of its divisors is an integer number (48731220).

Almost surely, 2^666403397 is an apocalyptic number.

It is an amenable number.

666403397 is a deficient number, since it is larger than the sum of its proper divisors (113296123).

666403397 is a wasteful number, since it uses less digits than its factorization.

666403397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60244.

The product of its (nonzero) digits is 489888, while the sum is 44.

The square root of 666403397 is about 25814.7902761188. The cubic root of 666403397 is about 873.4654559769.

The spelling of 666403397 in words is "six hundred sixty-six million, four hundred three thousand, three hundred ninety-seven".