666278703 has 40 divisors (see below), whose sum is σ = 1011056640. Its totient is φ = 437225040.

The previous prime is 666278699. The next prime is 666278737. The reversal of 666278703 is 307872666.

It is not a de Polignac number, because 666278703 - 2² = 666278699 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666278803) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 2458458 + ... + 2458728.

It is an arithmetic number, because the mean of its divisors is an integer number (25276416).

Almost surely, 2^666278703 is an apocalyptic number.

666278703 is a deficient number, since it is larger than the sum of its proper divisors (344777937).

666278703 is a wasteful number, since it uses less digits than its factorization.

666278703 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 649 (or 640 counting only the distinct ones).

The product of its (nonzero) digits is 508032, while the sum is 45.

The square root of 666278703 is about 25812.3749972760. The cubic root of 666278703 is about 873.4109731136.

The spelling of 666278703 in words is "six hundred sixty-six million, two hundred seventy-eight thousand, seven hundred three".