2091090421 has 16 divisors (see below), whose sum is σ = 2430604800. Its totient is φ = 1761971328.

The previous prime is 2091090403. The next prime is 2091090437. The reversal of 2091090421 is 1240901902.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 2091090421 - 2¹⁵ = 2091057653 is a prime.

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 2091090421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2091090481) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 120735 + ... + 136963.

It is an arithmetic number, because the mean of its divisors is an integer number (151912800).

Almost surely, 2^2091090421 is an apocalyptic number.

It is an amenable number.

2091090421 is a deficient number, since it is larger than the sum of its proper divisors (339514379).

2091090421 is a wasteful number, since it uses less digits than its factorization.

2091090421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16548.

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 2091090421 is about 45728.4421449058. The cubic root of 2091090421 is about 1278.7655785121.

The spelling of 2091090421 in words is "two billion, ninety-one million, ninety thousand, four hundred twenty-one".