669969897 has 4 divisors (see below), whose sum is σ = 893293200. Its totient is φ = 446646596.

The previous prime is 669969869. The next prime is 669969931. The reversal of 669969897 is 798969966.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 669969897 - 2²⁴ = 653192681 is a prime.

It is a super-3 number, since 3×669969897³ (a number of 27 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (669969497) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 111661647 + ... + 111661652.

It is an arithmetic number, because the mean of its divisors is an integer number (223323300).

Almost surely, 2^669969897 is an apocalyptic number.

It is an amenable number.

669969897 is a deficient number, since it is larger than the sum of its proper divisors (223323303).

669969897 is a wasteful number, since it uses less digits than its factorization.

669969897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 223323302.

The product of its digits is 79361856, while the sum is 69.

The square root of 669969897 is about 25883.7767143823. The cubic root of 669969897 is about 875.0209070379.

Adding to 669969897 its sum of digits (69), we get a palindrome (669969966).

The spelling of 669969897 in words is "six hundred sixty-nine million, nine hundred sixty-nine thousand, eight hundred ninety-seven".