21086265 has 8 divisors (see below), whose sum is σ = 33738048. Its totient is φ = 11246000.

The previous prime is 21086251. The next prime is 21086279. The reversal of 21086265 is 56268012.

It is an interprime number because it is at equal distance from previous prime (21086251) and next prime (21086279).

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

It is not a de Polignac number, because 21086265 - 2⁴ = 21086249 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 702861 + ... + 702890.

It is an arithmetic number, because the mean of its divisors is an integer number (4217256).

Almost surely, 2^21086265 is an apocalyptic number.

It is an amenable number.

21086265 is a deficient number, since it is larger than the sum of its proper divisors (12651783).

21086265 is a wasteful number, since it uses less digits than its factorization.

21086265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1405759.

The product of its (nonzero) digits is 5760, while the sum is 30.

The square root of 21086265 is about 4591.9783318304. The cubic root of 21086265 is about 276.2696770789.

The spelling of 21086265 in words is "twenty-one million, eighty-six thousand, two hundred sixty-five".