66898523 has 4 divisors (see below), whose sum is σ = 66920880. Its totient is φ = 66876168.

The previous prime is 66898493. The next prime is 66898537. The reversal of 66898523 is 32589866.

It is a happy number.

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 66898523 - 2⁶ = 66898459 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66898123) 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 in 3 ways as a sum of consecutive naturals, for example, 5840 + ... + 12957.

It is an arithmetic number, because the mean of its divisors is an integer number (16730220).

Almost surely, 2^66898523 is an apocalyptic number.

66898523 is a deficient number, since it is larger than the sum of its proper divisors (22357).

66898523 is a wasteful number, since it uses less digits than its factorization.

66898523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22356.

The product of its digits is 622080, while the sum is 47.

The square root of 66898523 is about 8179.1517286330. The cubic root of 66898523 is about 405.9496548346.

The spelling of 66898523 in words is "sixty-six million, eight hundred ninety-eight thousand, five hundred twenty-three".