82391909 has 2 divisors, whose sum is σ = 82391910. Its totient is φ = 82391908.

The previous prime is 82391899. The next prime is 82391917. The reversal of 82391909 is 90919328.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 68724100 + 13667809 = 8290^2 + 3697^2 .

It is a cyclic number.

It is not a de Polignac number, because 82391909 - 2²⁰ = 81343333 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (82394909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41195954 + 41195955.

It is an arithmetic number, because the mean of its divisors is an integer number (41195955).

Almost surely, 2^82391909 is an apocalyptic number.

It is an amenable number.

82391909 is a deficient number, since it is larger than the sum of its proper divisors (1).

82391909 is an equidigital number, since it uses as much as digits as its factorization.

82391909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 34992, while the sum is 41.

The square root of 82391909 is about 9076.9988983144. The cubic root of 82391909 is about 435.1391794922.

The spelling of 82391909 in words is "eighty-two million, three hundred ninety-one thousand, nine hundred nine".