66001006251 has 16 divisors (see below), whose sum is σ = 98112997920. Its totient is φ = 43850492640.

The previous prime is 66001006207. The next prime is 66001006259. The reversal of 66001006251 is 15260010066.

It is a happy number.

66001006251 is a `hidden beast` number, since 6 + 600 + 1 + 0 + 0 + 6 + 2 + 51 = 666.

It is not a de Polignac number, because 66001006251 - 2¹⁰ = 66001005227 is a prime.

It is a super-2 number, since 2×66001006251² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (66001006259) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4163560 + ... + 4179381.

It is an arithmetic number, because the mean of its divisors is an integer number (6132062370).

Almost surely, 2^66001006251 is an apocalyptic number.

66001006251 is a deficient number, since it is larger than the sum of its proper divisors (32111991669).

66001006251 is a wasteful number, since it uses less digits than its factorization.

66001006251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8343243 (or 8343237 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The spelling of 66001006251 in words is "sixty-six billion, one million, six thousand, two hundred fifty-one".