1664197254720 has 4200 divisors, whose sum is σ = 8655768491832. Its totient is φ = 300429803520.

The previous prime is 1664197254719. The next prime is 1664197254773. The reversal of 1664197254720 is 274527914661.

1664197254720 is a `hidden beast` number, since 1 + 6 + 6 + 4 + 1 + 9 + 72 + 547 + 20 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 121990929984 + 1542206324736 = 349272^2 + 1241856^2 .

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 599 ways as a sum of consecutive naturals, for example, 97893956152 + ... + 97893956168.

Almost surely, 2^{1664197254720} is an apocalyptic number.

1664197254720 is a gapful number since it is divisible by the number (10) 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 1664197254720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4327884245916).

1664197254720 is an abundant number, since it is smaller than the sum of its proper divisors (6991571237112).

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

1664197254720 is a wasteful number, since it uses less digits than its factorization.

1664197254720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109 (or 58 counting only the distinct ones).

The product of its (nonzero) digits is 5080320, while the sum is 54.

The spelling of 1664197254720 in words is "one trillion, six hundred sixty-four billion, one hundred ninety-seven million, two hundred fifty-four thousand, seven hundred twenty".