66143678 has 4 divisors (see below), whose sum is σ = 99215520. Its totient is φ = 33071838.

The previous prime is 66143669. The next prime is 66143681. The reversal of 66143678 is 87634166.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 87634166 = 2 ⋅43817083.

It is a super-2 number, since 2×66143678² = 8749972278735368, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16535918 + ... + 16535921.

It is an arithmetic number, because the mean of its divisors is an integer number (24803880).

Almost surely, 2^66143678 is an apocalyptic number.

66143678 is a deficient number, since it is larger than the sum of its proper divisors (33071842).

66143678 is a wasteful number, since it uses less digits than its factorization.

66143678 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33071841.

The product of its digits is 145152, while the sum is 41.

The square root of 66143678 is about 8132.8763669442. The cubic root of 66143678 is about 404.4170406759.

The spelling of 66143678 in words is "sixty-six million, one hundred forty-three thousand, six hundred seventy-eight".