66621254105280 has 1344 divisors, whose sum is σ = 259521555225600. Its totient is φ = 14417812684800.

The previous prime is 66621254105261. The next prime is 66621254105291. The reversal of 66621254105280 is 8250145212666.

It is a tau number, because it is divible by the number of its divisors (1344).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 14742474861 + ... + 14742479379.

Almost surely, 2^{66621254105280} is an apocalyptic number.

66621254105280 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 66621254105280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (129760777612800).

66621254105280 is an abundant number, since it is smaller than the sum of its proper divisors (192900301120320).

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

66621254105280 is a wasteful number, since it uses less digits than its factorization.

66621254105280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4790 (or 4773 counting only the distinct ones).

The product of its (nonzero) digits is 1382400, while the sum is 48.

The spelling of 66621254105280 in words is "sixty-six trillion, six hundred twenty-one billion, two hundred fifty-four million, one hundred five thousand, two hundred eighty".