6461618929920 has 1296 divisors, whose sum is σ = 29286867617280. Its totient is φ = 1299323289600.

The previous prime is 6461618929861. The next prime is 6461618929937. The reversal of 6461618929920 is 299298161646.

6461618929920 is a `hidden beast` number, since 6 + 4 + 6 + 1 + 618 + 9 + 2 + 9 + 9 + 2 + 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 (13) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 192470896 + ... + 192504464.

It is an arithmetic number, because the mean of its divisors is an integer number (22597891680).

Almost surely, 2^{6461618929920} is an apocalyptic number.

6461618929920 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 6461618929920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14643433808640).

6461618929920 is an abundant number, since it is smaller than the sum of its proper divisors (22825248687360).

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

6461618929920 is a wasteful number, since it uses less digits than its factorization.

6461618929920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33652 (or 33628 counting only the distinct ones).

The product of its (nonzero) digits is 20155392, while the sum is 63.

The spelling of 6461618929920 in words is "six trillion, four hundred sixty-one billion, six hundred eighteen million, nine hundred twenty-nine thousand, nine hundred twenty".