221534709945840 has 240 divisors, whose sum is σ = 745232729061600. Its totient is φ = 58977072580608.

The previous prime is 221534709945833. The next prime is 221534709945889. The reversal of 221534709945840 is 48549907435122.

It is a happy number.

221534709945840 is a `hidden beast` number, since 2 + 2 + 1 + 5 + 3 + 47 + 0 + 9 + 9 + 4 + 584 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2641395426 + ... + 2641479294.

It is an arithmetic number, because the mean of its divisors is an integer number (3105136371090).

Almost surely, 2^{221534709945840} is an apocalyptic number.

221534709945840 is a gapful number since it is divisible by the number (20) 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 221534709945840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (372616364530800).

221534709945840 is an abundant number, since it is smaller than the sum of its proper divisors (523698019115760).

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

221534709945840 is a wasteful number, since it uses less digits than its factorization.

221534709945840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89984 (or 89975 counting only the distinct ones).

The product of its (nonzero) digits is 87091200, while the sum is 63.

The spelling of 221534709945840 in words is "two hundred twenty-one trillion, five hundred thirty-four billion, seven hundred nine million, nine hundred forty-five thousand, eight hundred forty".