664801623332 has 108 divisors (see below), whose sum is σ = 1538859154140. Its totient is φ = 250081856640.

The previous prime is 664801623319. The next prime is 664801623371. The reversal of 664801623332 is 233326108466.

It can be written as a sum of positive squares in 2 ways, for example, as 564550865956 + 100250757376 = 751366^2 + 316624^2 .

It is a super-2 number, since 2×664801623332² (a number of 24 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 204458 + ... + 1171070.

Almost surely, 2^664801623332 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 664801623332, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (769429577070).

664801623332 is an abundant number, since it is smaller than the sum of its proper divisors (874057530808).

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

664801623332 is a wasteful number, since it uses less digits than its factorization.

664801623332 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 966682 (or 966662 counting only the distinct ones).

The product of its (nonzero) digits is 746496, while the sum is 44.

The spelling of 664801623332 in words is "six hundred sixty-four billion, eight hundred one million, six hundred twenty-three thousand, three hundred thirty-two".