53318021 has 2 divisors, whose sum is σ = 53318022. Its totient is φ = 53318020.

The previous prime is 53318017. The next prime is 53318039. The reversal of 53318021 is 12081335.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 32615521 + 20702500 = 5711^2 + 4550^2 .

It is a cyclic number.

It is not a de Polignac number, because 53318021 - 2² = 53318017 is a prime.

It is a super-2 number, since 2×53318021² = 5685622726712882, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (53318051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 26659010 + 26659011.

It is an arithmetic number, because the mean of its divisors is an integer number (26659011).

Almost surely, 2^53318021 is an apocalyptic number.

It is an amenable number.

53318021 is a deficient number, since it is larger than the sum of its proper divisors (1).

53318021 is an equidigital number, since it uses as much as digits as its factorization.

53318021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 53318021 is about 7301.9189943466. The cubic root of 53318021 is about 376.3783844609.

Adding to 53318021 its reverse (12081335), we get a palindrome (65399356).

The spelling of 53318021 in words is "fifty-three million, three hundred eighteen thousand, twenty-one".