221305377 has 16 divisors (see below), whose sum is σ = 300462912. Its totient is φ = 144851520.

The previous prime is 221305363. The next prime is 221305387. The reversal of 221305377 is 773503122.

It is not a de Polignac number, because 221305377 - 2⁴ = 221305361 is a prime.

It is a super-2 number, since 2×221305377² = 97952139778224258, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (221305327) 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, 172663 + ... + 173939.

It is an arithmetic number, because the mean of its divisors is an integer number (18778932).

Almost surely, 2^221305377 is an apocalyptic number.

It is an amenable number.

221305377 is a deficient number, since it is larger than the sum of its proper divisors (79157535).

221305377 is a wasteful number, since it uses less digits than its factorization.

221305377 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2288.

The product of its (nonzero) digits is 8820, while the sum is 30.

The square root of 221305377 is about 14876.3361416714. The cubic root of 221305377 is about 604.8727068667.

Adding to 221305377 its reverse (773503122), we get a palindrome (994808499).

The spelling of 221305377 in words is "two hundred twenty-one million, three hundred five thousand, three hundred seventy-seven".