83665612800 has 1560 divisors, whose sum is σ = 389340116352. Its totient is φ = 17252352000.

The previous prime is 83665612769. The next prime is 83665612801. The reversal of 83665612800 is 821656638.

83665612800 is a `hidden beast` number, since 8 + 3 + 6 + 6 + 561 + 2 + 80 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (83665612801) by changing a digit.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 638668735 + ... + 638668865.

Almost surely, 2^83665612800 is an apocalyptic number.

83665612800 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 83665612800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (194670058176).

83665612800 is an abundant number, since it is smaller than the sum of its proper divisors (305674503552).

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

83665612800 is a wasteful number, since it uses less digits than its factorization.

83665612800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 195 (or 159 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 45.

The spelling of 83665612800 in words is "eighty-three billion, six hundred sixty-five million, six hundred twelve thousand, eight hundred".