21455013 has 8 divisors (see below), whose sum is σ = 29304576. Its totient is φ = 13954400.

The previous prime is 21455011. The next prime is 21455023. The reversal of 21455013 is 31055412.

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 21455013 - 2¹ = 21455011 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21455011) 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 7 ways as a sum of consecutive naturals, for example, 87093 + ... + 87338.

It is an arithmetic number, because the mean of its divisors is an integer number (3663072).

Almost surely, 2^21455013 is an apocalyptic number.

It is an amenable number.

21455013 is a deficient number, since it is larger than the sum of its proper divisors (7849563).

21455013 is a wasteful number, since it uses less digits than its factorization.

21455013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 174475.

The product of its (nonzero) digits is 600, while the sum is 21.

The square root of 21455013 is about 4631.9556345026. The cubic root of 21455013 is about 277.8708101836.

The spelling of 21455013 in words is "twenty-one million, four hundred fifty-five thousand, thirteen".