221240684928 has 64 divisors (see below), whose sum is σ = 606627717120. Its totient is φ = 71367959040.

The previous prime is 221240684923. The next prime is 221240684933. The reversal of 221240684928 is 829486042122.

It is an interprime number because it is at equal distance from previous prime (221240684923) and next prime (221240684933).

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221240684923) 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 7 ways as a sum of consecutive naturals, for example, 9280800 + ... + 9304607.

It is an arithmetic number, because the mean of its divisors is an integer number (9478558080).

Almost surely, 2^221240684928 is an apocalyptic number.

It is an amenable number.

221240684928 is an abundant number, since it is smaller than the sum of its proper divisors (385387032192).

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

221240684928 is a wasteful number, since it uses less digits than its factorization.

221240684928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18585455 (or 18585443 counting only the distinct ones).

The product of its (nonzero) digits is 884736, while the sum is 48.

The spelling of 221240684928 in words is "two hundred twenty-one billion, two hundred forty million, six hundred eighty-four thousand, nine hundred twenty-eight".