2105515591 has 2 divisors, whose sum is σ = 2105515592. Its totient is φ = 2105515590.

The previous prime is 2105515561. The next prime is 2105515639. The reversal of 2105515591 is 1955155012.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2105515591 - 2⁷ = 2105515463 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2105515561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1052757795 + 1052757796.

It is an arithmetic number, because the mean of its divisors is an integer number (1052757796).

Almost surely, 2^2105515591 is an apocalyptic number.

2105515591 is a deficient number, since it is larger than the sum of its proper divisors (1).

2105515591 is an equidigital number, since it uses as much as digits as its factorization.

2105515591 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11250, while the sum is 34.

The square root of 2105515591 is about 45885.8975176470. The cubic root of 2105515591 is about 1281.6993199402.

The spelling of 2105515591 in words is "two billion, one hundred five million, five hundred fifteen thousand, five hundred ninety-one".