669349232640 has 1440 divisors, whose sum is σ = 2723582554560. Its totient is φ = 155713536000.

The previous prime is 669349232633. The next prime is 669349232647. The reversal of 669349232640 is 46232943966.

669349232640 is a `hidden beast` number, since 6 + 6 + 9 + 349 + 232 + 64 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (669349232633) and next prime (669349232647).

It is a tau number, because it is divible by the number of its divisors (1440).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (669349232647) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 10972938210 + ... + 10972938270.

It is an arithmetic number, because the mean of its divisors is an integer number (1891376774).

Almost surely, 2^669349232640 is an apocalyptic number.

669349232640 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 669349232640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1361791277280).

669349232640 is an abundant number, since it is smaller than the sum of its proper divisors (2054233321920).

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

669349232640 is a wasteful number, since it uses less digits than its factorization.

669349232640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166 (or 123 counting only the distinct ones).

The product of its (nonzero) digits is 10077696, while the sum is 54.

The spelling of 669349232640 in words is "six hundred sixty-nine billion, three hundred forty-nine million, two hundred thirty-two thousand, six hundred forty".