66673865398536 has 128 divisors (see below), whose sum is σ = 202082053132800. Its totient is φ = 20200197960000.

The previous prime is 66673865398513. The next prime is 66673865398537. The reversal of 66673865398536 is 63589356837666.

It is a super-2 number, since 2×66673865398536² (a number of 28 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (66673865398537) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 9223371 + ... + 14778981.

It is an arithmetic number, because the mean of its divisors is an integer number (1578766040100).

Almost surely, 2^{66673865398536} is an apocalyptic number.

66673865398536 is a gapful number since it is divisible by the number (66) 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 66673865398536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (101041026566400).

66673865398536 is an abundant number, since it is smaller than the sum of its proper divisors (135408187734264).

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

66673865398536 is a wasteful number, since it uses less digits than its factorization.

66673865398536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5560688 (or 5560678 counting only the distinct ones).

The product of its digits is 21163161600, while the sum is 81.

The spelling of 66673865398536 in words is "sixty-six trillion, six hundred seventy-three billion, eight hundred sixty-five million, three hundred ninety-eight thousand, five hundred thirty-six".