21148913 has 8 divisors (see below), whose sum is σ = 21885696. Its totient is φ = 20415600.

The previous prime is 21148879. The next prime is 21148921. The reversal of 21148913 is 31984112.

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 21148913 - 2¹⁸ = 20886769 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21148973) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19403 + ... + 20463.

It is an arithmetic number, because the mean of its divisors is an integer number (2735712).

Almost surely, 2^21148913 is an apocalyptic number.

It is an amenable number.

21148913 is a deficient number, since it is larger than the sum of its proper divisors (736783).

21148913 is a wasteful number, since it uses less digits than its factorization.

21148913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1735.

The product of its digits is 1728, while the sum is 29.

The square root of 21148913 is about 4598.7947334057. The cubic root of 21148913 is about 276.5430087214.

The spelling of 21148913 in words is "twenty-one million, one hundred forty-eight thousand, nine hundred thirteen".