51621121 has 2 divisors, whose sum is σ = 51621122. Its totient is φ = 51621120.

The previous prime is 51621079. The next prime is 51621127. The reversal of 51621121 is 12112615.

51621121 is an esthetic number in base 3, because in such base its adjacent digits differ by 1.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 49547521 + 2073600 = 7039^2 + 1440^2 .

It is a cyclic number.

It is not a de Polignac number, because 51621121 - 2¹³ = 51612929 is a prime.

It is equal to p_3092500 and since 51621121 and 3092500 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (51621127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25810560 + 25810561.

It is an arithmetic number, because the mean of its divisors is an integer number (25810561).

Almost surely, 2^51621121 is an apocalyptic number.

It is an amenable number.

51621121 is a deficient number, since it is larger than the sum of its proper divisors (1).

51621121 is an equidigital number, since it uses as much as digits as its factorization.

51621121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 120, while the sum is 19.

The square root of 51621121 is about 7184.7839911858. The cubic root of 51621121 is about 372.3423857609.

Adding to 51621121 its reverse (12112615), we get a palindrome (63733736).

The spelling of 51621121 in words is "fifty-one million, six hundred twenty-one thousand, one hundred twenty-one".