2215501891 has 2 divisors, whose sum is σ = 2215501892. Its totient is φ = 2215501890.

The previous prime is 2215501879. The next prime is 2215501901. The reversal of 2215501891 is 1981055122.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2215501891 - 2²⁵ = 2181947459 is a prime.

It is not a weakly prime, because it can be changed into another prime (2215501091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1107750945 + 1107750946.

It is an arithmetic number, because the mean of its divisors is an integer number (1107750946).

Almost surely, 2^2215501891 is an apocalyptic number.

2215501891 is a deficient number, since it is larger than the sum of its proper divisors (1).

2215501891 is an equidigital number, since it uses as much as digits as its factorization.

2215501891 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7200, while the sum is 34.

The square root of 2215501891 is about 47069.1182305341. The cubic root of 2215501891 is about 1303.6390917459.

The spelling of 2215501891 in words is "two billion, two hundred fifteen million, five hundred one thousand, eight hundred ninety-one".