53387821 has 2 divisors, whose sum is σ = 53387822. Its totient is φ = 53387820.

The previous prime is 53387809. The next prime is 53387827. The reversal of 53387821 is 12878335.

53387821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 49140100 + 4247721 = 7010^2 + 2061^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-53387821 is a prime.

It is a super-2 number, since 2×53387821² = 5700518862256082, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (53387827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 26693910 + 26693911.

It is an arithmetic number, because the mean of its divisors is an integer number (26693911).

Almost surely, 2^53387821 is an apocalyptic number.

It is an amenable number.

53387821 is a deficient number, since it is larger than the sum of its proper divisors (1).

53387821 is an equidigital number, since it uses as much as digits as its factorization.

53387821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 40320, while the sum is 37.

The square root of 53387821 is about 7306.6969965916. The cubic root of 53387821 is about 376.5425550670.

The spelling of 53387821 in words is "fifty-three million, three hundred eighty-seven thousand, eight hundred twenty-one".