2155205231 has 2 divisors, whose sum is σ = 2155205232. Its totient is φ = 2155205230.

The previous prime is 2155205203. The next prime is 2155205233. The reversal of 2155205231 is 1325025512.

2155205231 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2155205231 - 2⁶ = 2155205167 is a prime.

It is a super-2 number, since 2×2155205231² = 9289819175459526722, which contains 22 as substring.

Together with 2155205233, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2155205231.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2155205233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1077602615 + 1077602616.

It is an arithmetic number, because the mean of its divisors is an integer number (1077602616).

Almost surely, 2^2155205231 is an apocalyptic number.

2155205231 is a deficient number, since it is larger than the sum of its proper divisors (1).

2155205231 is an equidigital number, since it uses as much as digits as its factorization.

2155205231 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3000, while the sum is 26.

The square root of 2155205231 is about 46424.1879950528. The cubic root of 2155205231 is about 1291.7036223868.

The spelling of 2155205231 in words is "two billion, one hundred fifty-five million, two hundred five thousand, two hundred thirty-one".