669637091 has 8 divisors (see below), whose sum is σ = 675601920. Its totient is φ = 663683328.

The previous prime is 669637069. The next prime is 669637099. The reversal of 669637091 is 190736966.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 669637091 - 2¹⁸ = 669374947 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (669637099) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 160115 + ... + 164243.

It is an arithmetic number, because the mean of its divisors is an integer number (84450240).

Almost surely, 2^669637091 is an apocalyptic number.

669637091 is a deficient number, since it is larger than the sum of its proper divisors (5964829).

669637091 is a wasteful number, since it uses less digits than its factorization.

669637091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5533.

The product of its (nonzero) digits is 367416, while the sum is 47.

The square root of 669637091 is about 25877.3470626338. The cubic root of 669637091 is about 874.8759948350.

The spelling of 669637091 in words is "six hundred sixty-nine million, six hundred thirty-seven thousand, ninety-one".