669664572 has 12 divisors (see below), whose sum is σ = 1562550696. Its totient is φ = 223221520.

The previous prime is 669664571. The next prime is 669664579. The reversal of 669664572 is 275466966.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (669664571) 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, 27902679 + ... + 27902702.

It is an arithmetic number, because the mean of its divisors is an integer number (130212558).

Almost surely, 2^669664572 is an apocalyptic number.

It is an amenable number.

669664572 is an abundant number, since it is smaller than the sum of its proper divisors (892886124).

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

669664572 is a wasteful number, since it uses less digits than its factorization.

669664572 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55805388 (or 55805386 counting only the distinct ones).

The product of its digits is 3265920, while the sum is 51.

The square root of 669664572 is about 25877.8780428381. The cubic root of 669664572 is about 874.8879625802.

The spelling of 669664572 in words is "six hundred sixty-nine million, six hundred sixty-four thousand, five hundred seventy-two".