221127813 has 24 divisors (see below), whose sum is σ = 342669600. Its totient is φ = 142330608.

The previous prime is 221127793. The next prime is 221127817. The reversal of 221127813 is 318721122.

It is not a de Polignac number, because 221127813 - 2¹² = 221123717 is a prime.

It is a super-3 number, since 3×221127813³ (a number of 26 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221127817) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8643 + ... + 22736.

It is an arithmetic number, because the mean of its divisors is an integer number (14277900).

Almost surely, 2^221127813 is an apocalyptic number.

It is an amenable number.

221127813 is a deficient number, since it is larger than the sum of its proper divisors (121541787).

221127813 is an equidigital number, since it uses as much as digits as its factorization.

221127813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31423 (or 31411 counting only the distinct ones).

The product of its digits is 1344, while the sum is 27.

The square root of 221127813 is about 14870.3669423454. The cubic root of 221127813 is about 604.7108907123.

Adding to 221127813 its reverse (318721122), we get a palindrome (539848935).

The spelling of 221127813 in words is "two hundred twenty-one million, one hundred twenty-seven thousand, eight hundred thirteen".