669826206720 has 1056 divisors, whose sum is σ = 2688213415680. Its totient is φ = 152510791680.

The previous prime is 669826206689. The next prime is 669826206767. The reversal of 669826206720 is 27602628966.

669826206720 is a `hidden beast` number, since 6 + 6 + 9 + 8 + 2 + 620 + 6 + 7 + 2 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1056).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1512022819 + ... + 1512023261.

Almost surely, 2^669826206720 is an apocalyptic number.

669826206720 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 669826206720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1344106707840).

669826206720 is an abundant number, since it is smaller than the sum of its proper divisors (2018387208960).

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

669826206720 is a wasteful number, since it uses less digits than its factorization.

669826206720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 661 (or 640 counting only the distinct ones).

The product of its (nonzero) digits is 5225472, while the sum is 54.

The spelling of 669826206720 in words is "six hundred sixty-nine billion, eight hundred twenty-six million, two hundred six thousand, seven hundred twenty".