66146731840 has 112 divisors (see below), whose sum is σ = 181761944832. Its totient is φ = 22458617856.

The previous prime is 66146731829. The next prime is 66146731883. The reversal of 66146731840 is 4813764166.

It is a tau number, because it is divible by the number of its divisors (112).

It is a super-2 number, since 2×66146731840² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 87372 + ... + 374068.

Almost surely, 2^66146731840 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 66146731840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (90880972416).

66146731840 is an abundant number, since it is smaller than the sum of its proper divisors (115615212992).

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

66146731840 is a wasteful number, since it uses less digits than its factorization.

66146731840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 286824 (or 286814 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 46.

The spelling of 66146731840 in words is "sixty-six billion, one hundred forty-six million, seven hundred thirty-one thousand, eight hundred forty".