51156121 has 2 divisors, whose sum is σ = 51156122. Its totient is φ = 51156120.

The previous prime is 51156109. The next prime is 51156143. The reversal of 51156121 is 12165115.

It is a happy number.

It is an a-pointer prime, because the next prime (51156143) can be obtained adding 51156121 to its sum of digits (22).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 37650496 + 13505625 = 6136^2 + 3675^2 .

It is a cyclic number.

It is not a de Polignac number, because 51156121 - 2¹⁷ = 51025049 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 51156092 and 51156101.

It is not a weakly prime, because it can be changed into another prime (51156181) 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, 25578060 + 25578061.

It is an arithmetic number, because the mean of its divisors is an integer number (25578061).

Almost surely, 2^51156121 is an apocalyptic number.

It is an amenable number.

51156121 is a deficient number, since it is larger than the sum of its proper divisors (1).

51156121 is an equidigital number, since it uses as much as digits as its factorization.

51156121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 300, while the sum is 22.

The square root of 51156121 is about 7152.3507324515. The cubic root of 51156121 is about 371.2209991441.

It can be divided in two parts, 5115 and 6121, that added together give a square (11236 = 106²).

The spelling of 51156121 in words is "fifty-one million, one hundred fifty-six thousand, one hundred twenty-one".