21546913 has 16 divisors (see below), whose sum is σ = 23474880. Its totient is φ = 19728576.

The previous prime is 21546907. The next prime is 21546919. The reversal of 21546913 is 31964512.

It is an interprime number because it is at equal distance from previous prime (21546907) and next prime (21546919).

It is a cyclic number.

It is not a de Polignac number, because 21546913 - 2⁵ = 21546881 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21546919) 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 15 ways as a sum of consecutive naturals, for example, 45906 + ... + 46372.

It is an arithmetic number, because the mean of its divisors is an integer number (1467180).

Almost surely, 2^21546913 is an apocalyptic number.

It is an amenable number.

21546913 is a deficient number, since it is larger than the sum of its proper divisors (1927967).

21546913 is a wasteful number, since it uses less digits than its factorization.

21546913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 576.

The product of its digits is 6480, while the sum is 31.

The square root of 21546913 is about 4641.8652500907. The cubic root of 21546913 is about 278.2669872661.

The spelling of 21546913 in words is "twenty-one million, five hundred forty-six thousand, nine hundred thirteen".