669747966 has 16 divisors (see below), whose sum is σ = 1340835600. Its totient is φ = 223026048.

The previous prime is 669747961. The next prime is 669747973.

669747966 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×669747966² = 897124675922274312, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (669747961) 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, 49261 + ... + 61368.

It is an arithmetic number, because the mean of its divisors is an integer number (83802225).

Almost surely, 2^669747966 is an apocalyptic number.

669747966 is an abundant number, since it is smaller than the sum of its proper divisors (671087634).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

669747966 is a wasteful number, since it uses less digits than its factorization.

669747966 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111643.

The product of its digits is 20575296, while the sum is 60.

The square root of 669747966 is about 25879.4892917152. The cubic root of 669747966 is about 874.9242779643.

The spelling of 669747966 in words is "six hundred sixty-nine million, seven hundred forty-seven thousand, nine hundred sixty-six".