191666469941956 has 27 divisors (see below), whose sum is σ = 343400239338093. Its totient is φ = 93603973624560.

The previous prime is 191666469941929. The next prime is 191666469941987. The reversal of 191666469941956 is 659149964666191.

The square root of 191666469941956 is 13844366.

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., 155031534759556 + 36634935182400 = 12451166^2 + 6052680^2 .

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 191666469941956.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1190534986 + ... + 1190695966.

Almost surely, 2^{191666469941956} is an apocalyptic number.

191666469941956 is the 13844366-th square number.

It is an amenable number.

191666469941956 is a deficient number, since it is larger than the sum of its proper divisors (151733769396137).

191666469941956 is an frugal number, since it uses more digits than its factorization.

191666469941956 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 322052 (or 161026 counting only the distinct ones).

The product of its digits is 4081466880, while the sum is 82.

The spelling of 191666469941956 in words is "one hundred ninety-one trillion, six hundred sixty-six billion, four hundred sixty-nine million, nine hundred forty-one thousand, nine hundred fifty-six".