66943958 has 4 divisors (see below), whose sum is σ = 100415940. Its totient is φ = 33471978.

The previous prime is 66943957. The next prime is 66943963. The reversal of 66943958 is 85934966.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66943957) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16735988 + ... + 16735991.

It is an arithmetic number, because the mean of its divisors is an integer number (25103985).

Almost surely, 2^66943958 is an apocalyptic number.

66943958 is a deficient number, since it is larger than the sum of its proper divisors (33471982).

66943958 is a wasteful number, since it uses less digits than its factorization.

66943958 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33471981.

The product of its digits is 1399680, while the sum is 50.

The square root of 66943958 is about 8181.9287457176. The cubic root of 66943958 is about 406.0415360289.

The spelling of 66943958 in words is "sixty-six million, nine hundred forty-three thousand, nine hundred fifty-eight".