2155154777 has 2 divisors, whose sum is σ = 2155154778. Its totient is φ = 2155154776.

The previous prime is 2155154723. The next prime is 2155154783. The reversal of 2155154777 is 7774515512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1786668361 + 368486416 = 42269^2 + 19196^2 .

It is a cyclic number.

It is not a de Polignac number, because 2155154777 - 2⁶ = 2155154713 is a prime.

It is a super-2 number, since 2×2155154777² = 9289384225651839458, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (2155154707) 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, 1077577388 + 1077577389.

It is an arithmetic number, because the mean of its divisors is an integer number (1077577389).

Almost surely, 2^2155154777 is an apocalyptic number.

It is an amenable number.

2155154777 is a deficient number, since it is larger than the sum of its proper divisors (1).

2155154777 is an equidigital number, since it uses as much as digits as its factorization.

2155154777 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 343000, while the sum is 44.

The square root of 2155154777 is about 46423.6445897993. The cubic root of 2155154777 is about 1291.6935425852.

The spelling of 2155154777 in words is "two billion, one hundred fifty-five million, one hundred fifty-four thousand, seven hundred seventy-seven".