1090990081 has 4 divisors (see below), whose sum is σ = 1091423664. Its totient is φ = 1090556500.

The previous prime is 1090990067. The next prime is 1090990129. The reversal of 1090990081 is 1800990901.

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.

It is a cyclic number.

It is not a de Polignac number, because 1090990081 - 2⁷ = 1090989953 is a prime.

It is a super-2 number, since 2×1090990081² = 2380518713680773122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1090990081.

It is not an unprimeable number, because it can be changed into a prime (1090991081) 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, 212995 + ... + 218056.

It is an arithmetic number, because the mean of its divisors is an integer number (272855916).

Almost surely, 2^1090990081 is an apocalyptic number.

It is an amenable number.

1090990081 is a deficient number, since it is larger than the sum of its proper divisors (433583).

1090990081 is an equidigital number, since it uses as much as digits as its factorization.

1090990081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 433582.

The product of its (nonzero) digits is 5832, while the sum is 37.

The square root of 1090990081 is about 33030.1389794230. The cubic root of 1090990081 is about 1029.4539730082.

The spelling of 1090990081 in words is "one billion, ninety million, nine hundred ninety thousand, eighty-one".