84197819 has 2 divisors, whose sum is σ = 84197820. Its totient is φ = 84197818.

The previous prime is 84197783. The next prime is 84197831. The reversal of 84197819 is 91879148.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 84197819 - 2⁸ = 84197563 is a prime.

It is a super-2 number, since 2×84197819² = 14178545448713522, which contains 22 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (84197879) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42098909 + 42098910.

It is an arithmetic number, because the mean of its divisors is an integer number (42098910).

Almost surely, 2^84197819 is an apocalyptic number.

84197819 is a deficient number, since it is larger than the sum of its proper divisors (1).

84197819 is an equidigital number, since it uses as much as digits as its factorization.

84197819 is an evil number, because the sum of its binary digits is even.

The product of its digits is 145152, while the sum is 47.

The square root of 84197819 is about 9175.9369548837. The cubic root of 84197819 is about 438.2954349817.

The spelling of 84197819 in words is "eighty-four million, one hundred ninety-seven thousand, eight hundred nineteen".