66923231 has 4 divisors (see below), whose sum is σ = 66942864. Its totient is φ = 66903600.

The previous prime is 66923209. The next prime is 66923249. The reversal of 66923231 is 13232966.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13232966 = 2 ⋅6616483.

It is a cyclic number.

It is not a de Polignac number, because 66923231 - 2⁶ = 66923167 is a prime.

It is a super-2 number, since 2×66923231² = 8957437694958722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66923281) 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 3 ways as a sum of consecutive naturals, for example, 3230 + ... + 12011.

It is an arithmetic number, because the mean of its divisors is an integer number (16735716).

Almost surely, 2^66923231 is an apocalyptic number.

66923231 is a deficient number, since it is larger than the sum of its proper divisors (19633).

66923231 is a wasteful number, since it uses less digits than its factorization.

66923231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19632.

The product of its digits is 11664, while the sum is 32.

The square root of 66923231 is about 8180.6620147761. The cubic root of 66923231 is about 405.9996258904. Note that the first 3 decimals are identical.

The spelling of 66923231 in words is "sixty-six million, nine hundred twenty-three thousand, two hundred thirty-one".