11087213821 has 4 divisors (see below), whose sum is σ = 11123328832. Its totient is φ = 11051098812.

The previous prime is 11087213803. The next prime is 11087213827. The reversal of 11087213821 is 12831278011.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12831278011 = 163 ⋅78719497.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11087213821 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11087213827) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18057045 + ... + 18057658.

It is an arithmetic number, because the mean of its divisors is an integer number (2780832208).

Almost surely, 2^11087213821 is an apocalyptic number.

It is an amenable number.

11087213821 is a deficient number, since it is larger than the sum of its proper divisors (36115011).

11087213821 is an equidigital number, since it uses as much as digits as its factorization.

11087213821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36115010.

The product of its (nonzero) digits is 5376, while the sum is 34.

The spelling of 11087213821 in words is "eleven billion, eighty-seven million, two hundred thirteen thousand, eight hundred twenty-one".