51120749 has 2 divisors, whose sum is σ = 51120750. Its totient is φ = 51120748.

The previous prime is 51120739. The next prime is 51120761. The reversal of 51120749 is 94702115.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 41860900 + 9259849 = 6470^2 + 3043^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51120749 is a prime.

It is a super-2 number, since 2×51120749² = 5226661956642002, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51120739) 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, 25560374 + 25560375.

It is an arithmetic number, because the mean of its divisors is an integer number (25560375).

Almost surely, 2^51120749 is an apocalyptic number.

It is an amenable number.

51120749 is a deficient number, since it is larger than the sum of its proper divisors (1).

51120749 is an equidigital number, since it uses as much as digits as its factorization.

51120749 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2520, while the sum is 29.

The square root of 51120749 is about 7149.8775513990. The cubic root of 51120749 is about 371.1354189207.

The spelling of 51120749 in words is "fifty-one million, one hundred twenty thousand, seven hundred forty-nine".