83121561600 has 1008 divisors, whose sum is σ = 350164213056. Its totient is φ = 17203200000.

The previous prime is 83121561581. The next prime is 83121561613. The reversal of 83121561600 is 616512138.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 331161475 + ... + 331161725.

It is an arithmetic number, because the mean of its divisors is an integer number (347385132).

Almost surely, 2^83121561600 is an apocalyptic number.

83121561600 is a gapful number since it is divisible by the number (80) 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 83121561600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (175082106528).

83121561600 is an abundant number, since it is smaller than the sum of its proper divisors (267042651456).

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

83121561600 is a wasteful number, since it uses less digits than its factorization.

83121561600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 315 (or 279 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 33.

The spelling of 83121561600 in words is "eighty-three billion, one hundred twenty-one million, five hundred sixty-one thousand, six hundred".