1918131511 has 2 divisors, whose sum is σ = 1918131512. Its totient is φ = 1918131510.

The previous prime is 1918131493. The next prime is 1918131521. The reversal of 1918131511 is 1151318191.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1918131511 - 2⁹ = 1918130999 is a prime.

It is a super-2 number, since 2×1918131511² = 7358456986982286242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1918131521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 959065755 + 959065756.

It is an arithmetic number, because the mean of its divisors is an integer number (959065756).

Almost surely, 2^1918131511 is an apocalyptic number.

1918131511 is a deficient number, since it is larger than the sum of its proper divisors (1).

1918131511 is an equidigital number, since it uses as much as digits as its factorization.

1918131511 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1080, while the sum is 31.

The square root of 1918131511 is about 43796.4782944930. The cubic root of 1918131511 is about 1242.4896889001.

The spelling of 1918131511 in words is "one billion, nine hundred eighteen million, one hundred thirty-one thousand, five hundred eleven".