51117397 has 2 divisors, whose sum is σ = 51117398. Its totient is φ = 51117396.

The previous prime is 51117383. The next prime is 51117421. The reversal of 51117397 is 79371115.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38825361 + 12292036 = 6231^2 + 3506^2 .

It is a cyclic number.

It is not a de Polignac number, because 51117397 - 2²³ = 42728789 is a prime.

It is a super-2 number, since 2×51117397² = 5225976552111218, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51117307) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25558698 + 25558699.

It is an arithmetic number, because the mean of its divisors is an integer number (25558699).

Almost surely, 2^51117397 is an apocalyptic number.

It is an amenable number.

51117397 is a deficient number, since it is larger than the sum of its proper divisors (1).

51117397 is an equidigital number, since it uses as much as digits as its factorization.

51117397 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 51117397 is about 7149.6431379475. The cubic root of 51117397 is about 371.1273069301.

The spelling of 51117397 in words is "fifty-one million, one hundred seventeen thousand, three hundred ninety-seven".