651618880 has 84 divisors (see below), whose sum is σ = 1705653180. Its totient is φ = 236938240.

The previous prime is 651618871. The next prime is 651618887. The reversal of 651618880 is 88816156.

651618880 = 3415² + 3416² + ... + 3469².

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 95413824 + 556205056 = 9768^2 + 23584^2 .

It is not an unprimeable number, because it can be changed into a prime (651618887) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 30306 + ... + 47134.

It is an arithmetic number, because the mean of its divisors is an integer number (20305395).

Almost surely, 2^651618880 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 651618880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (852826590).

651618880 is an abundant number, since it is smaller than the sum of its proper divisors (1054034300).

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

651618880 is a wasteful number, since it uses less digits than its factorization.

651618880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16868 (or 16847 counting only the distinct ones).

The product of its (nonzero) digits is 92160, while the sum is 43.

The square root of 651618880 is about 25526.8266731296. The cubic root of 651618880 is about 866.9576563963.

The spelling of 651618880 in words is "six hundred fifty-one million, six hundred eighteen thousand, eight hundred eighty".