53891221 has 2 divisors, whose sum is σ = 53891222. Its totient is φ = 53891220.

The previous prime is 53891209. The next prime is 53891267. The reversal of 53891221 is 12219835.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 39828721 + 14062500 = 6311^2 + 3750^2 .

It is a cyclic number.

It is not a de Polignac number, because 53891221 - 2¹³ = 53883029 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (53891291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 26945610 + 26945611.

It is an arithmetic number, because the mean of its divisors is an integer number (26945611).

Almost surely, 2^53891221 is an apocalyptic number.

It is an amenable number.

53891221 is a deficient number, since it is larger than the sum of its proper divisors (1).

53891221 is an equidigital number, since it uses as much as digits as its factorization.

53891221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4320, while the sum is 31.

The square root of 53891221 is about 7341.0640236957. The cubic root of 53891221 is about 377.7223425931.

The spelling of 53891221 in words is "fifty-three million, eight hundred ninety-one thousand, two hundred twenty-one".