221395849 has 4 divisors (see below), whose sum is σ = 221965380. Its totient is φ = 220826320.

The previous prime is 221395843. The next prime is 221395871. The reversal of 221395849 is 948593122.

221395849 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 157954624 + 63441225 = 12568^2 + 7965^2 .

It is a cyclic number.

It is not a de Polignac number, because 221395849 - 2¹⁵ = 221363081 is a prime.

It is a super-2 number, since 2×221395849² = 98032243908861602, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221395843) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 284182 + ... + 284959.

It is an arithmetic number, because the mean of its divisors is an integer number (55491345).

Almost surely, 2^221395849 is an apocalyptic number.

It is an amenable number.

221395849 is a deficient number, since it is larger than the sum of its proper divisors (569531).

221395849 is an equidigital number, since it uses as much as digits as its factorization.

221395849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 569530.

The product of its digits is 155520, while the sum is 43.

The square root of 221395849 is about 14879.3766334481. The cubic root of 221395849 is about 604.9551217764.

The spelling of 221395849 in words is "two hundred twenty-one million, three hundred ninety-five thousand, eight hundred forty-nine".