1088664821 has 4 divisors (see below), whose sum is σ = 1100897100. Its totient is φ = 1076432544.

The previous prime is 1088664799. The next prime is 1088664893. The reversal of 1088664821 is 1284668801.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 585156100 + 503508721 = 24190^2 + 22439^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1088664821 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 (1088669821) 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, 6116006 + ... + 6116183.

It is an arithmetic number, because the mean of its divisors is an integer number (275224275).

Almost surely, 2^1088664821 is an apocalyptic number.

It is an amenable number.

1088664821 is a deficient number, since it is larger than the sum of its proper divisors (12232279).

1088664821 is an equidigital number, since it uses as much as digits as its factorization.

1088664821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12232278.

The product of its (nonzero) digits is 147456, while the sum is 44.

The square root of 1088664821 is about 32994.9211394724. The cubic root of 1088664821 is about 1028.7220840491.

The spelling of 1088664821 in words is "one billion, eighty-eight million, six hundred sixty-four thousand, eight hundred twenty-one".