221072688 has 60 divisors (see below), whose sum is σ = 645606000. Its totient is φ = 70485888.

The previous prime is 221072651. The next prime is 221072729. The reversal of 221072688 is 886270122.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 30063 + ... + 36686.

It is an arithmetic number, because the mean of its divisors is an integer number (10760100).

Almost surely, 2^221072688 is an apocalyptic number.

It is an amenable number.

221072688 is an abundant number, since it is smaller than the sum of its proper divisors (424533312).

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

221072688 is a wasteful number, since it uses less digits than its factorization.

221072688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66786 (or 66777 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The square root of 221072688 is about 14868.5133083305. The cubic root of 221072688 is about 604.6606370335.

The spelling of 221072688 in words is "two hundred twenty-one million, seventy-two thousand, six hundred eighty-eight".