65999251 has 2 divisors, whose sum is σ = 65999252. Its totient is φ = 65999250.

The previous prime is 65999249. The next prime is 65999291. The reversal of 65999251 is 15299956.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 65999251 - 2¹ = 65999249 is a prime.

It is a super-3 number, since 3×65999251³ (a number of 24 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

Together with 65999249, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (65999291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32999625 + 32999626.

It is an arithmetic number, because the mean of its divisors is an integer number (32999626).

Almost surely, 2^65999251 is an apocalyptic number.

65999251 is a deficient number, since it is larger than the sum of its proper divisors (1).

65999251 is an equidigital number, since it uses as much as digits as its factorization.

65999251 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 218700, while the sum is 46.

The square root of 65999251 is about 8123.9923067418. The cubic root of 65999251 is about 404.1224733247.

The spelling of 65999251 in words is "sixty-five million, nine hundred ninety-nine thousand, two hundred fifty-one".