82191001 has 2 divisors, whose sum is σ = 82191002. Its totient is φ = 82191000.

The previous prime is 82190989. The next prime is 82191007. The reversal of 82191001 is 10019128.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 81920601 + 270400 = 9051^2 + 520^2 .

It is a cyclic number.

It is not a de Polignac number, because 82191001 - 2⁹ = 82190489 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (82191007) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41095500 + 41095501.

It is an arithmetic number, because the mean of its divisors is an integer number (41095501).

Almost surely, 2^82191001 is an apocalyptic number.

It is an amenable number.

82191001 is a deficient number, since it is larger than the sum of its proper divisors (1).

82191001 is an equidigital number, since it uses as much as digits as its factorization.

82191001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 22.

The square root of 82191001 is about 9065.9252699325. The cubic root of 82191001 is about 434.7852042116.

The spelling of 82191001 in words is "eighty-two million, one hundred ninety-one thousand, one".