2156478871 has 2 divisors, whose sum is σ = 2156478872. Its totient is φ = 2156478870.

The previous prime is 2156478847. The next prime is 2156478887. The reversal of 2156478871 is 1788746512.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2156478871 - 2⁷ = 2156478743 is a prime.

It is a super-2 number, since 2×2156478871² = 9300802242138869282, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2156478671) 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, 1078239435 + 1078239436.

It is an arithmetic number, because the mean of its divisors is an integer number (1078239436).

Almost surely, 2^2156478871 is an apocalyptic number.

2156478871 is a deficient number, since it is larger than the sum of its proper divisors (1).

2156478871 is an equidigital number, since it uses as much as digits as its factorization.

2156478871 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 752640, while the sum is 49.

The square root of 2156478871 is about 46437.9033872116. The cubic root of 2156478871 is about 1291.9580206545.

The spelling of 2156478871 in words is "two billion, one hundred fifty-six million, four hundred seventy-eight thousand, eight hundred seventy-one".