1151831111 has 2 divisors, whose sum is σ = 1151831112. Its totient is φ = 1151831110.

The previous prime is 1151831063. The next prime is 1151831113. The reversal of 1151831111 is 1111381511.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1151831111 - 2⁶ = 1151831047 is a prime.

It is a Sophie Germain prime.

Together with 1151831113, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1151831113) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 575915555 + 575915556.

It is an arithmetic number, because the mean of its divisors is an integer number (575915556).

Almost surely, 2^1151831111 is an apocalyptic number.

1151831111 is a deficient number, since it is larger than the sum of its proper divisors (1).

1151831111 is an equidigital number, since it uses as much as digits as its factorization.

1151831111 is an evil number, because the sum of its binary digits is even.

The product of its digits is 120, while the sum is 23.

The square root of 1151831111 is about 33938.6374358194. The cubic root of 1151831111 is about 1048.2453266622.

Subtracting from 1151831111 its reverse (1111381511), we obtain a square (40449600 = 6360²).

The spelling of 1151831111 in words is "one billion, one hundred fifty-one million, eight hundred thirty-one thousand, one hundred eleven".