53723221 has 2 divisors, whose sum is σ = 53723222. Its totient is φ = 53723220.

The previous prime is 53723191. The next prime is 53723227. The reversal of 53723221 is 12232735.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 53144100 + 579121 = 7290^2 + 761^2 .

It is a cyclic number.

It is not a de Polignac number, because 53723221 - 2¹³ = 53715029 is a prime.

It is a super-2 number, since 2×53723221² = 5772368949229682, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (53723227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 26861610 + 26861611.

It is an arithmetic number, because the mean of its divisors is an integer number (26861611).

Almost surely, 2^53723221 is an apocalyptic number.

It is an amenable number.

53723221 is a deficient number, since it is larger than the sum of its proper divisors (1).

53723221 is an equidigital number, since it uses as much as digits as its factorization.

53723221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2520, while the sum is 25.

The square root of 53723221 is about 7329.6126091356. The cubic root of 53723221 is about 377.3294312971.

Adding to 53723221 its reverse (12232735), we get a palindrome (65955956).

The spelling of 53723221 in words is "fifty-three million, seven hundred twenty-three thousand, two hundred twenty-one".