2156518277 has 2 divisors, whose sum is σ = 2156518278. Its totient is φ = 2156518276.

The previous prime is 2156518253. The next prime is 2156518283. The reversal of 2156518277 is 7728156512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2135733796 + 20784481 = 46214^2 + 4559^2 .

It is a cyclic number.

It is not a de Polignac number, because 2156518277 - 2¹² = 2156514181 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2156512277) 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, 1078259138 + 1078259139.

It is an arithmetic number, because the mean of its divisors is an integer number (1078259139).

Almost surely, 2^2156518277 is an apocalyptic number.

It is an amenable number.

2156518277 is a deficient number, since it is larger than the sum of its proper divisors (1).

2156518277 is an equidigital number, since it uses as much as digits as its factorization.

2156518277 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 235200, while the sum is 44.

The square root of 2156518277 is about 46438.3276723010. The cubic root of 2156518277 is about 1291.9658900550.

The spelling of 2156518277 in words is "two billion, one hundred fifty-six million, five hundred eighteen thousand, two hundred seventy-seven".