21291485 has 8 divisors (see below), whose sum is σ = 25613280. Its totient is φ = 16990864.

The previous prime is 21291467. The next prime is 21291499. The reversal of 21291485 is 58419212.

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 21291485 - 2¹² = 21287389 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, 2987 + ... + 7176.

It is an arithmetic number, because the mean of its divisors is an integer number (3201660).

Almost surely, 2^21291485 is an apocalyptic number.

It is an amenable number.

21291485 is a deficient number, since it is larger than the sum of its proper divisors (4321795).

21291485 is a wasteful number, since it uses less digits than its factorization.

21291485 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10587.

The product of its digits is 5760, while the sum is 32.

The square root of 21291485 is about 4614.2697147003. The cubic root of 21291485 is about 277.1630409438.

The spelling of 21291485 in words is "twenty-one million, two hundred ninety-one thousand, four hundred eighty-five".