221626240 has 64 divisors (see below), whose sum is σ = 578009520. Its totient is φ = 80588800.

The previous prime is 221626217. The next prime is 221626247. The reversal of 221626240 is 42626122.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221626247) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8701 + ... + 22780.

Almost surely, 2^221626240 is an apocalyptic number.

221626240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221626240 is an abundant number, since it is smaller than the sum of its proper divisors (356383280).

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

221626240 is a wasteful number, since it uses less digits than its factorization.

221626240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31511 (or 31499 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 221626240 is about 14887.1165777662. The cubic root of 221626240 is about 605.1648936965.

The spelling of 221626240 in words is "two hundred twenty-one million, six hundred twenty-six thousand, two hundred forty".