66659503 has 4 divisors (see below), whose sum is σ = 68209768. Its totient is φ = 65109240.

The previous prime is 66659501. The next prime is 66659507. The reversal of 66659503 is 30595666.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66659503 - 2¹ = 66659501 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 (66659501) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 775068 + ... + 775153.

It is an arithmetic number, because the mean of its divisors is an integer number (17052442).

Almost surely, 2^66659503 is an apocalyptic number.

66659503 is a deficient number, since it is larger than the sum of its proper divisors (1550265).

66659503 is a wasteful number, since it uses less digits than its factorization.

66659503 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1550264.

The product of its (nonzero) digits is 145800, while the sum is 40.

The square root of 66659503 is about 8164.5271142914. The cubic root of 66659503 is about 405.4656088954.

The spelling of 66659503 in words is "sixty-six million, six hundred fifty-nine thousand, five hundred three".