669389808983965 has 8 divisors (see below), whose sum is σ = 803281244038488. Its totient is φ = 535502865015360.

The previous prime is 669389808983963. The next prime is 669389808983993. The reversal of 669389808983965 is 569389808983966.

It can be written as a sum of positive squares in 4 ways, for example, as 127354768514649 + 542035040469316 = 11285157^2 + 23281646^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 669389808983965 - 2¹ = 669389808983963 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (669389808983963) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1122443562 + ... + 1123039771.

It is an arithmetic number, because the mean of its divisors is an integer number (100410155504811).

Almost surely, 2^{669389808983965} is an apocalyptic number.

It is an amenable number.

669389808983965 is a deficient number, since it is larger than the sum of its proper divisors (133891435054523).

669389808983965 is a wasteful number, since it uses less digits than its factorization.

669389808983965 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2245542959.

The product of its (nonzero) digits is 261213880320, while the sum is 97.

Subtracting from 669389808983965 its reverse (569389808983966), we obtain a palindrome (99999999999999).

The spelling of 669389808983965 in words is "six hundred sixty-nine trillion, three hundred eighty-nine billion, eight hundred eight million, nine hundred eighty-three thousand, nine hundred sixty-five".