66375721402452 has 432 divisors, whose sum is σ = 216036644503680. Its totient is φ = 16810912419840.

The previous prime is 66375721402451. The next prime is 66375721402541. The reversal of 66375721402452 is 25420412757366.

66375721402452 is a `hidden beast` number, since 6 + 6 + 3 + 7 + 572 + 1 + 40 + 24 + 5 + 2 = 666.

It is a super-2 number, since 2×66375721402452² (a number of 28 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66375721402451) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 777472824 + ... + 777558192.

It is an arithmetic number, because the mean of its divisors is an integer number (500084825240).

Almost surely, 2^{66375721402452} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66375721402452, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (108018322251840).

66375721402452 is an abundant number, since it is smaller than the sum of its proper divisors (149660923101228).

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

66375721402452 is a wasteful number, since it uses less digits than its factorization.

66375721402452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86044 (or 86028 counting only the distinct ones).

The product of its (nonzero) digits is 16934400, while the sum is 54.

The spelling of 66375721402452 in words is "sixty-six trillion, three hundred seventy-five billion, seven hundred twenty-one million, four hundred two thousand, four hundred fifty-two".