51397117 has 2 divisors, whose sum is σ = 51397118. Its totient is φ = 51397116.

The previous prime is 51397081. The next prime is 51397127. The reversal of 51397117 is 71179315.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 48594841 + 2802276 = 6971^2 + 1674^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51397117 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51397127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25698558 + 25698559.

It is an arithmetic number, because the mean of its divisors is an integer number (25698559).

Almost surely, 2^51397117 is an apocalyptic number.

It is an amenable number.

51397117 is a deficient number, since it is larger than the sum of its proper divisors (1).

51397117 is an equidigital number, since it uses as much as digits as its factorization.

51397117 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6615, while the sum is 34.

The square root of 51397117 is about 7169.1782653244. The cubic root of 51397117 is about 371.8030256583.

The spelling of 51397117 in words is "fifty-one million, three hundred ninety-seven thousand, one hundred seventeen".