1011111111 has 12 divisors (see below), whose sum is σ = 1476905040. Its totient is φ = 666499680.

The previous prime is 1011111083. The next prime is 1011111133. The reversal of 1011111111 is 1111111101.

It is not a de Polignac number, because 1011111111 - 2¹³ = 1011102919 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

1011111111 is a modest number, since divided by 11111 gives 10111 as remainder.

It is a junction number, because it is equal to n+sod(n) for n = 1011111093 and 1011111102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1011113111) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 630355 + ... + 631956.

It is an arithmetic number, because the mean of its divisors is an integer number (123075420).

Almost surely, 2^1011111111 is an apocalyptic number.

1011111111 is a deficient number, since it is larger than the sum of its proper divisors (465793929).

1011111111 is a wasteful number, since it uses less digits than its factorization.

1011111111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1262406 (or 1262403 counting only the distinct ones).

The product of its (nonzero) digits is 1, while the sum is 9.

The square root of 1011111111 is about 31797.9733788177. The cubic root of 1011111111 is about 1003.6900702991.

Adding to 1011111111 its reverse (1111111101), we get a palindrome (2122222212).

It can be divided in two parts, 101 and 1111111, that multiplied together give a palindrome (112222211).

The spelling of 1011111111 in words is "one billion, eleven million, one hundred eleven thousand, one hundred eleven".