2118457391 has 2 divisors, whose sum is σ = 2118457392. Its totient is φ = 2118457390.

The previous prime is 2118457387. The next prime is 2118457403. The reversal of 2118457391 is 1937548112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2118457391 - 2² = 2118457387 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2118457301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1059228695 + 1059228696.

It is an arithmetic number, because the mean of its divisors is an integer number (1059228696).

Almost surely, 2^2118457391 is an apocalyptic number.

2118457391 is a deficient number, since it is larger than the sum of its proper divisors (1).

2118457391 is an equidigital number, since it uses as much as digits as its factorization.

2118457391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 60480, while the sum is 41.

The square root of 2118457391 is about 46026.7030211811. The cubic root of 2118457391 is about 1284.3199965166.

The spelling of 2118457391 in words is "two billion, one hundred eighteen million, four hundred fifty-seven thousand, three hundred ninety-one".