51020197 has 2 divisors, whose sum is σ = 51020198. Its totient is φ = 51020196.

The previous prime is 51020173. The next prime is 51020201. The reversal of 51020197 is 79102015.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 32821441 + 18198756 = 5729^2 + 4266^2 .

It is a cyclic number.

It is not a de Polignac number, because 51020197 - 2⁷ = 51020069 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51020107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25510098 + 25510099.

It is an arithmetic number, because the mean of its divisors is an integer number (25510099).

Almost surely, 2^51020197 is an apocalyptic number.

It is an amenable number.

51020197 is a deficient number, since it is larger than the sum of its proper divisors (1).

51020197 is an equidigital number, since it uses as much as digits as its factorization.

51020197 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 630, while the sum is 25.

The square root of 51020197 is about 7142.8423614133. The cubic root of 51020197 is about 370.8919241626.

The spelling of 51020197 in words is "fifty-one million, twenty thousand, one hundred ninety-seven".