221161797 has 12 divisors (see below), whose sum is σ = 320118240. Its totient is φ = 147135528.

The previous prime is 221161793. The next prime is 221161817. The reversal of 221161797 is 797161122.

It is a happy number.

221161797 is a `hidden beast` number, since 22 + 11 + 617 + 9 + 7 = 666.

221161797 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 221161797 - 2² = 221161793 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221161793) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 20847 + ... + 29612.

It is an arithmetic number, because the mean of its divisors is an integer number (26676520).

Almost surely, 2^221161797 is an apocalyptic number.

It is an amenable number.

221161797 is a deficient number, since it is larger than the sum of its proper divisors (98956443).

221161797 is a wasteful number, since it uses less digits than its factorization.

221161797 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50952 (or 50949 counting only the distinct ones).

The product of its digits is 10584, while the sum is 36.

The square root of 221161797 is about 14871.5095736781. The cubic root of 221161797 is about 604.7418674311.

The spelling of 221161797 in words is "two hundred twenty-one million, one hundred sixty-one thousand, seven hundred ninety-seven".