61641216000 has 1664 divisors, whose sum is σ = 286226304000. Its totient is φ = 13005619200.

The previous prime is 61641215981. The next prime is 61641216023. The reversal of 61641216000 is 61214616.

61641216000 is a `hidden beast` number, since 6 + 1 + 641 + 2 + 16 + 0 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1664).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 4741631994 + ... + 4741632006.

It is an arithmetic number, because the mean of its divisors is an integer number (172011000).

Almost surely, 2^61641216000 is an apocalyptic number.

61641216000 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 61641216000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (143113152000).

61641216000 is an abundant number, since it is smaller than the sum of its proper divisors (224585088000).

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

61641216000 is an equidigital number, since it uses as much as digits as its factorization.

61641216000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82 (or 30 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The spelling of 61641216000 in words is "sixty-one billion, six hundred forty-one million, two hundred sixteen thousand".