221660090 has 8 divisors (see below), whose sum is σ = 398988180. Its totient is φ = 88664032.

The previous prime is 221660077. The next prime is 221660113. The reversal of 221660090 is 90066122.

It can be written as a sum of positive squares in 2 ways, for example, as 219128809 + 2531281 = 14803^2 + 1591^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

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, 11082995 + ... + 11083014.

Almost surely, 2^221660090 is an apocalyptic number.

221660090 is a deficient number, since it is larger than the sum of its proper divisors (177328090).

221660090 is a wasteful number, since it uses less digits than its factorization.

221660090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22166016.

The product of its (nonzero) digits is 1296, while the sum is 26.

The square root of 221660090 is about 14888.2534234208. The cubic root of 221660090 is about 605.1957020052.

The spelling of 221660090 in words is "two hundred twenty-one million, six hundred sixty thousand, ninety".