66156287 has 4 divisors (see below), whose sum is σ = 67277640. Its totient is φ = 65034936.

The previous prime is 66156283. The next prime is 66156289. The reversal of 66156287 is 78265166.

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 66156287 - 2² = 66156283 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66156283) 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, 560588 + ... + 560705.

It is an arithmetic number, because the mean of its divisors is an integer number (16819410).

Almost surely, 2^66156287 is an apocalyptic number.

66156287 is a deficient number, since it is larger than the sum of its proper divisors (1121353).

66156287 is a wasteful number, since it uses less digits than its factorization.

66156287 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1121352.

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

The square root of 66156287 is about 8133.6515170002. The cubic root of 66156287 is about 404.4427371125.

The spelling of 66156287 in words is "sixty-six million, one hundred fifty-six thousand, two hundred eighty-seven".