221794810379520 has 576 divisors, whose sum is σ = 819587147366400. Its totient is φ = 50071057956864.

The previous prime is 221794810379507. The next prime is 221794810379521. The reversal of 221794810379520 is 25973018497122.

It is a super-2 number, since 2×221794810379520² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221794810379521) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 761122806 + ... + 761414154.

Almost surely, 2^{221794810379520} is an apocalyptic number.

221794810379520 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 221794810379520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (409793573683200).

221794810379520 is an abundant number, since it is smaller than the sum of its proper divisors (597792336986880).

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

221794810379520 is a wasteful number, since it uses less digits than its factorization.

221794810379520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 291730 (or 291716 counting only the distinct ones).

The product of its (nonzero) digits is 15240960, while the sum is 60.

The spelling of 221794810379520 in words is "two hundred twenty-one trillion, seven hundred ninety-four billion, eight hundred ten million, three hundred seventy-nine thousand, five hundred twenty".