66719376885249 has 45 divisors (see below), whose sum is σ = 109552897254801. Its totient is φ = 40435495899480.

The previous prime is 66719376885193. The next prime is 66719376885353. The reversal of 66719376885249 is 94258867391766.

The square root of 66719376885249 is 8168193.

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

66719376885249 is a `hidden beast` number, since 6 + 6 + 7 + 1 + 9 + 3 + 7 + 6 + 88 + 524 + 9 = 666.

It is not a de Polignac number, because 66719376885249 - 2¹⁹ = 66719376360961 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (81).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (66719376885449) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 808609854 + ... + 808692360.

Almost surely, 2^{66719376885249} is an apocalyptic number.

66719376885249 is the 8168193-rd square number.

66719376885249 is the 4084097-th centered octagonal number.

It is an amenable number.

66719376885249 is a deficient number, since it is larger than the sum of its proper divisors (42833520369552).

66719376885249 is an frugal number, since it uses more digits than its factorization.

66719376885249 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165048 (or 82521 counting only the distinct ones).

The product of its digits is 6584094720, while the sum is 81.

66719376885249 divided by its sum of digits (81) gives a square (823696010929 = 907577²).

The spelling of 66719376885249 in words is "sixty-six trillion, seven hundred nineteen billion, three hundred seventy-six million, eight hundred eighty-five thousand, two hundred forty-nine".