21082855 has 8 divisors (see below), whose sum is σ = 26172000. Its totient is φ = 16284576.

The previous prime is 21082849. The next prime is 21082861. The reversal of 21082855 is 55828012.

It is an interprime number because it is at equal distance from previous prime (21082849) and next prime (21082861).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21082855 - 2³ = 21082847 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 72555 + ... + 72844.

It is an arithmetic number, because the mean of its divisors is an integer number (3271500).

Almost surely, 2^21082855 is an apocalyptic number.

21082855 is a deficient number, since it is larger than the sum of its proper divisors (5089145).

21082855 is a wasteful number, since it uses less digits than its factorization.

21082855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145433.

The product of its (nonzero) digits is 6400, while the sum is 31.

The square root of 21082855 is about 4591.6070171564. The cubic root of 21082855 is about 276.2547838077.

The spelling of 21082855 in words is "twenty-one million, eighty-two thousand, eight hundred fifty-five".