66516278 has 4 divisors (see below), whose sum is σ = 99774420. Its totient is φ = 33258138.

The previous prime is 66516271. The next prime is 66516293. The reversal of 66516278 is 87261566.

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 (66516271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16629068 + ... + 16629071.

It is an arithmetic number, because the mean of its divisors is an integer number (24943605).

Almost surely, 2^66516278 is an apocalyptic number.

66516278 is a deficient number, since it is larger than the sum of its proper divisors (33258142).

66516278 is a wasteful number, since it uses less digits than its factorization.

66516278 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33258141.

The product of its digits is 120960, while the sum is 41.

The square root of 66516278 is about 8155.7512222971. The cubic root of 66516278 is about 405.1750054016.

The spelling of 66516278 in words is "sixty-six million, five hundred sixteen thousand, two hundred seventy-eight".