66397523 has 4 divisors (see below), whose sum is σ = 66528480. Its totient is φ = 66266568.

The previous prime is 66397453. The next prime is 66397531. The reversal of 66397523 is 32579366.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66397523 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66390523) 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, 64715 + ... + 65732.

It is an arithmetic number, because the mean of its divisors is an integer number (16632120).

Almost surely, 2^66397523 is an apocalyptic number.

66397523 is a deficient number, since it is larger than the sum of its proper divisors (130957).

66397523 is a wasteful number, since it uses less digits than its factorization.

66397523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130956.

The product of its digits is 204120, while the sum is 41.

The square root of 66397523 is about 8148.4675246331. The cubic root of 66397523 is about 404.9337350306.

The spelling of 66397523 in words is "sixty-six million, three hundred ninety-seven thousand, five hundred twenty-three".