667755990720 has 3024 divisors, whose sum is σ = 3228839778528. Its totient is φ = 130427781120.

The previous prime is 667755990719. The next prime is 667755990751. The reversal of 667755990720 is 27099557766.

667755990720 is a `hidden beast` number, since 6 + 6 + 7 + 7 + 559 + 9 + 0 + 72 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (3024).

It is a super-2 number, since 2×667755990720² (a number of 24 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is an unprimeable number.

It is a polite number, since it can be written in 431 ways as a sum of consecutive naturals, for example, 10946819490 + ... + 10946819550.

It is an arithmetic number, because the mean of its divisors is an integer number (1067738022).

Almost surely, 2^667755990720 is an apocalyptic number.

667755990720 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 667755990720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1614419889264).

667755990720 is an abundant number, since it is smaller than the sum of its proper divisors (2561083787808).

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

667755990720 is a wasteful number, since it uses less digits than its factorization.

667755990720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150 (or 108 counting only the distinct ones).

The product of its (nonzero) digits is 50009400, while the sum is 63.

The spelling of 667755990720 in words is "six hundred sixty-seven billion, seven hundred fifty-five million, nine hundred ninety thousand, seven hundred twenty".