669767102449 has 3 divisors (see below), whose sum is σ = 669767920843. Its totient is φ = 669766284056.

The previous prime is 669767102447. The next prime is 669767102491. The reversal of 669767102449 is 944201767966.

The square root of 669767102449 is 818393.

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

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 204326600625 + 465440501824 = 452025^2 + 682232^2 .

It is not a de Polignac number, because 669767102449 - 2¹ = 669767102447 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (669767102443) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 409197 + ... + 1227589.

Almost surely, 2^669767102449 is an apocalyptic number.

669767102449 is the 818393-rd square number.

669767102449 is the 409197-th centered octagonal number.

It is an amenable number.

669767102449 is a deficient number, since it is larger than the sum of its proper divisors (818394).

669767102449 is an frugal number, since it uses more digits than its factorization.

669767102449 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1636786 (or 818393 counting only the distinct ones).

The product of its (nonzero) digits is 27433728, while the sum is 61.

The spelling of 669767102449 in words is "six hundred sixty-nine billion, seven hundred sixty-seven million, one hundred two thousand, four hundred forty-nine".