53551021 has 2 divisors, whose sum is σ = 53551022. Its totient is φ = 53551020.

The previous prime is 53551009. The next prime is 53551027. The reversal of 53551021 is 12015535.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 53436100 + 114921 = 7310^2 + 339^2 .

It is a cyclic number.

It is not a de Polignac number, because 53551021 - 2⁵ = 53550989 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 53550983 and 53551001.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (53551027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 26775510 + 26775511.

It is an arithmetic number, because the mean of its divisors is an integer number (26775511).

Almost surely, 2^53551021 is an apocalyptic number.

It is an amenable number.

53551021 is a deficient number, since it is larger than the sum of its proper divisors (1).

53551021 is an equidigital number, since it uses as much as digits as its factorization.

53551021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 750, while the sum is 22.

The square root of 53551021 is about 7317.8563117897. The cubic root of 53551021 is about 376.9258461944.

Adding to 53551021 its reverse (12015535), we get a palindrome (65566556).

The spelling of 53551021 in words is "fifty-three million, five hundred fifty-one thousand, twenty-one".