1091881615 has 12 divisors (see below), whose sum is σ = 1440201672. Its totient is φ = 794095280.

The previous prime is 1091881613. The next prime is 1091881633. The reversal of 1091881615 is 5161881901.

It is not a de Polignac number, because 1091881615 - 2¹ = 1091881613 is a prime.

It is a super-3 number, since 3×1091881615³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1091881613) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 901777 + ... + 902986.

It is an arithmetic number, because the mean of its divisors is an integer number (120016806).

Almost surely, 2^1091881615 is an apocalyptic number.

1091881615 is a deficient number, since it is larger than the sum of its proper divisors (348320057).

1091881615 is a wasteful number, since it uses less digits than its factorization.

1091881615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1804790 (or 1804779 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 40.

The square root of 1091881615 is about 33043.6319886298. The cubic root of 1091881615 is about 1029.7343126579.

The spelling of 1091881615 in words is "one billion, ninety-one million, eight hundred eighty-one thousand, six hundred fifteen".