66990198040516 has 9 divisors (see below), whose sum is σ = 117232875217549. Its totient is φ = 33495090835504.

The previous prime is 66990198040481. The next prime is 66990198040607. The reversal of 66990198040516 is 61504089109966.

The square root of 66990198040516 is 8184754.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 22256787644100 + 44733410396416 = 4717710^2 + 6688304^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 14323320 + ... + 18415696.

Almost surely, 2^{66990198040516} is an apocalyptic number.

66990198040516 is the 8184754-th square number.

It is an amenable number.

66990198040516 is a deficient number, since it is larger than the sum of its proper divisors (50242677177033).

66990198040516 is an frugal number, since it uses more digits than its factorization.

66990198040516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8184758 (or 4092379 counting only the distinct ones).

The product of its (nonzero) digits is 25194240, while the sum is 64.

The spelling of 66990198040516 in words is "sixty-six trillion, nine hundred ninety billion, one hundred ninety-eight million, forty thousand, five hundred sixteen".