2156561203 has 2 divisors, whose sum is σ = 2156561204. Its totient is φ = 2156561202.

The previous prime is 2156561189. The next prime is 2156561257. The reversal of 2156561203 is 3021656512.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2156561203 - 2¹³ = 2156553011 is a prime.

It is not a weakly prime, because it can be changed into another prime (2156561293) 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, 1078280601 + 1078280602.

It is an arithmetic number, because the mean of its divisors is an integer number (1078280602).

Almost surely, 2^2156561203 is an apocalyptic number.

2156561203 is a deficient number, since it is larger than the sum of its proper divisors (1).

2156561203 is an equidigital number, since it uses as much as digits as its factorization.

2156561203 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10800, while the sum is 31.

The square root of 2156561203 is about 46438.7898528805. The cubic root of 2156561203 is about 1291.9744622924.

The spelling of 2156561203 in words is "two billion, one hundred fifty-six million, five hundred sixty-one thousand, two hundred three".