2154967891 has 2 divisors, whose sum is σ = 2154967892. Its totient is φ = 2154967890.

The previous prime is 2154967879. The next prime is 2154967939. The reversal of 2154967891 is 1987694512.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2154967891 - 2²¹ = 2152870739 is a prime.

It is a super-2 number, since 2×2154967891² = 9287773222481975762, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (2154968891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1077483945 + 1077483946.

It is an arithmetic number, because the mean of its divisors is an integer number (1077483946).

Almost surely, 2^2154967891 is an apocalyptic number.

2154967891 is a deficient number, since it is larger than the sum of its proper divisors (1).

2154967891 is an equidigital number, since it uses as much as digits as its factorization.

2154967891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1088640, while the sum is 52.

The square root of 2154967891 is about 46421.6317141050. The cubic root of 2154967891 is about 1291.6562047537.

The spelling of 2154967891 in words is "two billion, one hundred fifty-four million, nine hundred sixty-seven thousand, eight hundred ninety-one".