51109901 has 2 divisors, whose sum is σ = 51109902. Its totient is φ = 51109900.

The previous prime is 51109879. The next prime is 51109907. The reversal of 51109901 is 10990115.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 46594276 + 4515625 = 6826^2 + 2125^2 .

It is a cyclic number.

It is not a de Polignac number, because 51109901 - 2¹⁸ = 50847757 is a prime.

It is a super-2 number, since 2×51109901² = 5224443960459602, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51109907) 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, 25554950 + 25554951.

It is an arithmetic number, because the mean of its divisors is an integer number (25554951).

Almost surely, 2^51109901 is an apocalyptic number.

It is an amenable number.

51109901 is a deficient number, since it is larger than the sum of its proper divisors (1).

51109901 is an equidigital number, since it uses as much as digits as its factorization.

51109901 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 405, while the sum is 26.

The square root of 51109901 is about 7149.1188967592. The cubic root of 51109901 is about 371.1091649898.

The spelling of 51109901 in words is "fifty-one million, one hundred nine thousand, nine hundred one".