664526550 has 48 divisors (see below), whose sum is σ = 1658197440. Its totient is φ = 176113440.

The previous prime is 664526543. The next prime is 664526563. The reversal of 664526550 is 55625466.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 664526499 and 664526508.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10861 + ... + 38039.

It is an arithmetic number, because the mean of its divisors is an integer number (34545780).

Almost surely, 2^664526550 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 664526550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (829098720).

664526550 is an abundant number, since it is smaller than the sum of its proper divisors (993670890).

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

664526550 is a wasteful number, since it uses less digits than its factorization.

664526550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27357 (or 27352 counting only the distinct ones).

The product of its (nonzero) digits is 216000, while the sum is 39.

The square root of 664526550 is about 25778.4124802130. The cubic root of 664526550 is about 872.6446806211.

The spelling of 664526550 in words is "six hundred sixty-four million, five hundred twenty-six thousand, five hundred fifty".