66217352372 has 6 divisors (see below), whose sum is σ = 115880366658. Its totient is φ = 33108676184.

The previous prime is 66217352363. The next prime is 66217352407. The reversal of 66217352372 is 27325371266.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 58978065316 + 7239287056 = 242854^2 + 85084^2 .

It is a super-2 number, since 2×66217352372² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8277169043 + ... + 8277169050.

It is an arithmetic number, because the mean of its divisors is an integer number (19313394443).

Almost surely, 2^66217352372 is an apocalyptic number.

It is an amenable number.

66217352372 is a deficient number, since it is larger than the sum of its proper divisors (49663014286).

66217352372 is a wasteful number, since it uses less digits than its factorization.

66217352372 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16554338097 (or 16554338095 counting only the distinct ones).

The product of its digits is 635040, while the sum is 44.

The spelling of 66217352372 in words is "sixty-six billion, two hundred seventeen million, three hundred fifty-two thousand, three hundred seventy-two".