66125133617 has 8 divisors (see below), whose sum is σ = 67787769672. Its totient is φ = 64464870400.

The previous prime is 66125133611. The next prime is 66125133671. The reversal of 66125133617 is 71633152166.

It can be written as a sum of positive squares in 4 ways, for example, as 1102173601 + 65022960016 = 33199^2 + 254996^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66125133617 - 2¹⁶ = 66125068081 is a prime.

It is a super-2 number, since 2×66125133617² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66125133611) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 536708 + ... + 648309.

It is an arithmetic number, because the mean of its divisors is an integer number (8473471209).

Almost surely, 2^66125133617 is an apocalyptic number.

It is an amenable number.

66125133617 is a deficient number, since it is larger than the sum of its proper divisors (1662636055).

66125133617 is a wasteful number, since it uses less digits than its factorization.

66125133617 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1186419.

The product of its digits is 136080, while the sum is 41.

The spelling of 66125133617 in words is "sixty-six billion, one hundred twenty-five million, one hundred thirty-three thousand, six hundred seventeen".