1091911026 has 16 divisors (see below), whose sum is σ = 2193617664. Its totient is φ = 362337744.

The previous prime is 1091911013. The next prime is 1091911027. The reversal of 1091911026 is 6201191901.

It is a junction number, because it is equal to n+sod(n) for n = 1091910984 and 1091911002.

It is not an unprimeable number, because it can be changed into a prime (1091911027) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 406701 + ... + 409376.

It is an arithmetic number, because the mean of its divisors is an integer number (137101104).

Almost surely, 2^1091911026 is an apocalyptic number.

1091911026 is an abundant number, since it is smaller than the sum of its proper divisors (1101706638).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1091911026 is a wasteful number, since it uses less digits than its factorization.

1091911026 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 816305.

The product of its (nonzero) digits is 972, while the sum is 30.

The square root of 1091911026 is about 33044.0770184310. The cubic root of 1091911026 is about 1029.7435582402.

It can be divided in two parts, 10919 and 11026, that added together give a triangular number (21945 = T₂₀₉).

The spelling of 1091911026 in words is "one billion, ninety-one million, nine hundred eleven thousand, twenty-six".