21082311 has 6 divisors (see below), whose sum is σ = 30452240. Its totient is φ = 14054868.

The previous prime is 21082309. The next prime is 21082319. The reversal of 21082311 is 11328012.

It is not a de Polignac number, because 21082311 - 2¹ = 21082309 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 (21082319) 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 5 ways as a sum of consecutive naturals, for example, 1171231 + ... + 1171248.

Almost surely, 2^21082311 is an apocalyptic number.

21082311 is a deficient number, since it is larger than the sum of its proper divisors (9369929).

21082311 is a wasteful number, since it uses less digits than its factorization.

21082311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2342485 (or 2342482 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

The square root of 21082311 is about 4591.5477782552. The cubic root of 21082311 is about 276.2524077239.

The spelling of 21082311 in words is "twenty-one million, eighty-two thousand, three hundred eleven".