664399458450 has 576 divisors, whose sum is σ = 2398303165440. Its totient is φ = 132798839040.

The previous prime is 664399458427. The next prime is 664399458493. The reversal of 664399458450 is 54854993466.

664399458450 is a `hidden beast` number, since 6 + 6 + 43 + 9 + 9 + 4 + 584 + 5 + 0 = 666.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 20991537 + ... + 21023163.

Almost surely, 2^664399458450 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 664399458450, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1199151582720).

664399458450 is an abundant number, since it is smaller than the sum of its proper divisors (1733903706990).

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

664399458450 is a wasteful number, since it uses less digits than its factorization.

664399458450 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31693 (or 31676 counting only the distinct ones).

The product of its (nonzero) digits is 111974400, while the sum is 63.

The spelling of 664399458450 in words is "six hundred sixty-four billion, three hundred ninety-nine million, four hundred fifty-eight thousand, four hundred fifty".