21080349 has 12 divisors (see below), whose sum is σ = 30690816. Its totient is φ = 13942152.

The previous prime is 21080333. The next prime is 21080369. The reversal of 21080349 is 94308012.

It is not a de Polignac number, because 21080349 - 2⁴ = 21080333 is a prime.

It is a super-2 number, since 2×21080349² = 888762227923602, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21080369) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8079 + ... + 10364.

It is an arithmetic number, because the mean of its divisors is an integer number (2557568).

Almost surely, 2^21080349 is an apocalyptic number.

It is an amenable number.

21080349 is a deficient number, since it is larger than the sum of its proper divisors (9610467).

21080349 is a wasteful number, since it uses less digits than its factorization.

21080349 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18576 (or 18573 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 21080349 is about 4591.3341198392. The cubic root of 21080349 is about 276.2438377583.

The spelling of 21080349 in words is "twenty-one million, eighty thousand, three hundred forty-nine".