736221 has 4 divisors (see below), whose sum is σ = 981632. Its totient is φ = 490812.

The previous prime is 736187. The next prime is 736243. The reversal of 736221 is 122637.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 122637 = 3 ⋅40879.

It is not a de Polignac number, because 736221 - 2⁷ = 736093 is a prime.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (736121) 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, 122701 + ... + 122706.

It is an arithmetic number, because the mean of its divisors is an integer number (245408).

2⁷³⁶²²¹ is an apocalyptic number.

It is an amenable number.

736221 is a deficient number, since it is larger than the sum of its proper divisors (245411).

736221 is a wasteful number, since it uses less digits than its factorization.

736221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 245410.

The product of its digits is 504, while the sum is 21.

The square root of 736221 is about 858.0332161403. The cubic root of 736221 is about 90.2961846982.

Adding to 736221 its reverse (122637), we get a palindrome (858858).

The spelling of 736221 in words is "seven hundred thirty-six thousand, two hundred twenty-one".