82161251 has 2 divisors, whose sum is σ = 82161252. Its totient is φ = 82161250.

The previous prime is 82161241. The next prime is 82161259. The reversal of 82161251 is 15216128.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 82161251 - 2¹⁸ = 81899107 is a prime.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 82161251.

It is not a weakly prime, because it can be changed into another prime (82161259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41080625 + 41080626.

It is an arithmetic number, because the mean of its divisors is an integer number (41080626).

Almost surely, 2^82161251 is an apocalyptic number.

82161251 is a deficient number, since it is larger than the sum of its proper divisors (1).

82161251 is an equidigital number, since it uses as much as digits as its factorization.

82161251 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 960, while the sum is 26.

The square root of 82161251 is about 9064.2843622649. The cubic root of 82161251 is about 434.7327393407.

Adding to 82161251 its reverse (15216128), we get a palindrome (97377379).

The spelling of 82161251 in words is "eighty-two million, one hundred sixty-one thousand, two hundred fifty-one".