221031097 has 16 divisors (see below), whose sum is σ = 255388672. Its totient is φ = 187382160.

The previous prime is 221031089. The next prime is 221031101. The reversal of 221031097 is 790130122.

It is not a de Polignac number, because 221031097 - 2³ = 221031089 is a prime.

It is not an unprimeable number, because it can be changed into a prime (221031017) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 349972 + ... + 350602.

It is an arithmetic number, because the mean of its divisors is an integer number (15961792).

Almost surely, 2^221031097 is an apocalyptic number.

It is an amenable number.

221031097 is a deficient number, since it is larger than the sum of its proper divisors (34357575).

221031097 is a wasteful number, since it uses less digits than its factorization.

221031097 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1108.

The product of its (nonzero) digits is 756, while the sum is 25.

The square root of 221031097 is about 14867.1146158224. The cubic root of 221031097 is about 604.6227158441.

The spelling of 221031097 in words is "two hundred twenty-one million, thirty-one thousand, ninety-seven".