661834100659200 has 1584 divisors, whose sum is σ = 2568961307203200. Its totient is φ = 149830678609920.

The previous prime is 661834100659183. The next prime is 661834100659201. The reversal of 661834100659200 is 2956001438166.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661834100659201) 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, 174488292504 + ... + 174488296296.

Almost surely, 2^{661834100659200} is an apocalyptic number.

661834100659200 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 661834100659200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1284480653601600).

661834100659200 is an abundant number, since it is smaller than the sum of its proper divisors (1907127206544000).

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

661834100659200 is a wasteful number, since it uses less digits than its factorization.

661834100659200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4272 (or 4242 counting only the distinct ones).

The product of its (nonzero) digits is 1866240, while the sum is 51.

The spelling of 661834100659200 in words is "six hundred sixty-one trillion, eight hundred thirty-four billion, one hundred million, six hundred fifty-nine thousand, two hundred".