7898943391 has 2 divisors, whose sum is σ = 7898943392. Its totient is φ = 7898943390.

The previous prime is 7898943361. The next prime is 7898943401. The reversal of 7898943391 is 1933498987.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7898943391 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7898943301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3949471695 + 3949471696.

It is an arithmetic number, because the mean of its divisors is an integer number (3949471696).

Almost surely, 2^7898943391 is an apocalyptic number.

7898943391 is a deficient number, since it is larger than the sum of its proper divisors (1).

7898943391 is an equidigital number, since it uses as much as digits as its factorization.

7898943391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11757312, while the sum is 61.

The square root of 7898943391 is about 88876.0000843872. Note that the first 4 decimals coincide. The cubic root of 7898943391 is about 1991.5429050956.

The spelling of 7898943391 in words is "seven billion, eight hundred ninety-eight million, nine hundred forty-three thousand, three hundred ninety-one".