8495221391 has 2 divisors, whose sum is σ = 8495221392. Its totient is φ = 8495221390.

The previous prime is 8495221387. The next prime is 8495221393. The reversal of 8495221391 is 1931225948.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 8495221391 - 2² = 8495221387 is a prime.

Together with 8495221393, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8495221393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4247610695 + 4247610696.

It is an arithmetic number, because the mean of its divisors is an integer number (4247610696).

Almost surely, 2^8495221391 is an apocalyptic number.

8495221391 is a deficient number, since it is larger than the sum of its proper divisors (1).

8495221391 is an equidigital number, since it uses as much as digits as its factorization.

8495221391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 155520, while the sum is 44.

The square root of 8495221391 is about 92169.5252835773. The cubic root of 8495221391 is about 2040.4450354676.

The spelling of 8495221391 in words is "eight billion, four hundred ninety-five million, two hundred twenty-one thousand, three hundred ninety-one".