66888231 has 4 divisors (see below), whose sum is σ = 89184312. Its totient is φ = 44592152.

The previous prime is 66888229. The next prime is 66888247. The reversal of 66888231 is 13288866.

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 66888231 - 2¹ = 66888229 is a prime.

It is a super-2 number, since 2×66888231² = 8948070892618722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66888271) 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, 11148036 + ... + 11148041.

It is an arithmetic number, because the mean of its divisors is an integer number (22296078).

Almost surely, 2^66888231 is an apocalyptic number.

66888231 is a deficient number, since it is larger than the sum of its proper divisors (22296081).

66888231 is a wasteful number, since it uses less digits than its factorization.

66888231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22296080.

The product of its digits is 110592, while the sum is 42.

The square root of 66888231 is about 8178.5225438339. The cubic root of 66888231 is about 405.9288359987.

The spelling of 66888231 in words is "sixty-six million, eight hundred eighty-eight thousand, two hundred thirty-one".