651660660 has 192 divisors, whose sum is σ = 2453552640. Its totient is φ = 140175360.

The previous prime is 651660623. The next prime is 651660661. The reversal of 651660660 is 66066156.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (651660661) by changing a digit.

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 63 ways as a sum of consecutive naturals, for example, 59190 + ... + 69330.

It is an arithmetic number, because the mean of its divisors is an integer number (12778920).

Almost surely, 2^651660660 is an apocalyptic number.

651660660 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 651660660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1226776320).

651660660 is an abundant number, since it is smaller than the sum of its proper divisors (1801891980).

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

651660660 is a wasteful number, since it uses less digits than its factorization.

651660660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10183 (or 10175 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 36.

The square root of 651660660 is about 25527.6450147678. The cubic root of 651660660 is about 866.9761849758.

It can be divided in two parts, 6516 and 60660, that added together give a palindrome (67176).

The spelling of 651660660 in words is "six hundred fifty-one million, six hundred sixty thousand, six hundred sixty".