221766140 has 12 divisors (see below), whose sum is σ = 465708936. Its totient is φ = 88706448.

The previous prime is 221766137. The next prime is 221766169. The reversal of 221766140 is 41667122.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5544134 + ... + 5544173.

It is an arithmetic number, because the mean of its divisors is an integer number (38809078).

Almost surely, 2^221766140 is an apocalyptic number.

221766140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221766140 is an abundant number, since it is smaller than the sum of its proper divisors (243942796).

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

221766140 is a wasteful number, since it uses less digits than its factorization.

221766140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11088316 (or 11088314 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 29.

The square root of 221766140 is about 14891.8145301370. The cubic root of 221766140 is about 605.2922022689.

The spelling of 221766140 in words is "two hundred twenty-one million, seven hundred sixty-six thousand, one hundred forty".