66641521500 has 1152 divisors, whose sum is σ = 257467392000. Its totient is φ = 14805504000.

The previous prime is 66641521487. The next prime is 66641521501. The reversal of 66641521500 is 512514666.

66641521500 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 (66641521501) by changing a digit.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 2149726485 + ... + 2149726515.

It is an arithmetic number, because the mean of its divisors is an integer number (223496000).

Almost surely, 2^66641521500 is an apocalyptic number.

66641521500 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 66641521500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (128733696000).

66641521500 is an abundant number, since it is smaller than the sum of its proper divisors (190825870500).

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

66641521500 is a wasteful number, since it uses less digits than its factorization.

66641521500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 141 (or 106 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 36.

The spelling of 66641521500 in words is "sixty-six billion, six hundred forty-one million, five hundred twenty-one thousand, five hundred".