66267645251 has 4 divisors (see below), whose sum is σ = 66279201912. Its totient is φ = 66256088592.

The previous prime is 66267645229. The next prime is 66267645361. The reversal of 66267645251 is 15254676266.

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 66267645251 - 2¹⁸ = 66267383107 is a prime.

It is a super-2 number, since 2×66267645251² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66267645251.

It is not an unprimeable number, because it can be changed into a prime (66267645151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5769725 + ... + 5781198.

It is an arithmetic number, because the mean of its divisors is an integer number (16569800478).

Almost surely, 2^66267645251 is an apocalyptic number.

66267645251 is a deficient number, since it is larger than the sum of its proper divisors (11556661).

66267645251 is a wasteful number, since it uses less digits than its factorization.

66267645251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11556660.

The product of its digits is 3628800, while the sum is 50.

The spelling of 66267645251 in words is "sixty-six billion, two hundred sixty-seven million, six hundred forty-five thousand, two hundred fifty-one".