51891017 has 2 divisors, whose sum is σ = 51891018. Its totient is φ = 51891016.

The previous prime is 51891011. The next prime is 51891029. The reversal of 51891017 is 71019815.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 49900096 + 1990921 = 7064^2 + 1411^2 .

It is a cyclic number.

It is not a de Polignac number, because 51891017 - 2¹² = 51886921 is a prime.

It is not a weakly prime, because it can be changed into another prime (51891011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25945508 + 25945509.

It is an arithmetic number, because the mean of its divisors is an integer number (25945509).

Almost surely, 2^51891017 is an apocalyptic number.

It is an amenable number.

51891017 is a deficient number, since it is larger than the sum of its proper divisors (1).

51891017 is an equidigital number, since it uses as much as digits as its factorization.

51891017 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2520, while the sum is 32.

The square root of 51891017 is about 7203.5419760004. The cubic root of 51891017 is about 372.9901767233.

The spelling of 51891017 in words is "fifty-one million, eight hundred ninety-one thousand, seventeen".