664081567744 has 351 divisors, whose sum is σ = 1656514609113. Its totient is φ = 265361424384.

The previous prime is 664081567741. The next prime is 664081567783. The reversal of 664081567744 is 447765180466.

The square root of 664081567744 is 814912.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 517018521600 + 147063046144 = 719040^2 + 383488^2 .

It is a super-2 number, since 2×664081567744² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (664081567741) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 6206369739 + ... + 6206369845.

Almost surely, 2^664081567744 is an apocalyptic number.

664081567744 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

664081567744 is the 814912-nd square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 664081567744

664081567744 is an abundant number, since it is smaller than the sum of its proper divisors (992433041369).

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

664081567744 is an equidigital number, since it uses as much as digits as its factorization.

664081567744 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 286 (or 133 counting only the distinct ones).

The product of its (nonzero) digits is 27095040, while the sum is 58.

The spelling of 664081567744 in words is "six hundred sixty-four billion, eighty-one million, five hundred sixty-seven thousand, seven hundred forty-four".