221009721492 has 192 divisors, whose sum is σ = 620993028096. Its totient is φ = 59849487360.

The previous prime is 221009721397. The next prime is 221009721539. The reversal of 221009721492 is 294127900122.

221009721492 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 221009721492.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 166547733 + ... + 166549059.

It is an arithmetic number, because the mean of its divisors is an integer number (3234338688).

Almost surely, 2^221009721492 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 221009721492, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (310496514048).

221009721492 is an abundant number, since it is smaller than the sum of its proper divisors (399983306604).

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

221009721492 is a wasteful number, since it uses less digits than its factorization.

221009721492 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2726 (or 2724 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 39.

The spelling of 221009721492 in words is "two hundred twenty-one billion, nine million, seven hundred twenty-one thousand, four hundred ninety-two".