21198613 has 8 divisors (see below), whose sum is σ = 21761696. Its totient is φ = 20638800.

The previous prime is 21198559. The next prime is 21198631. The reversal of 21198613 is 31689112.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21198613 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21198673) by changing a digit.

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, 17518 + ... + 18688.

It is an arithmetic number, because the mean of its divisors is an integer number (2720212).

Almost surely, 2^21198613 is an apocalyptic number.

It is an amenable number.

21198613 is a deficient number, since it is larger than the sum of its proper divisors (563083).

21198613 is a wasteful number, since it uses less digits than its factorization.

21198613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1635.

The product of its digits is 2592, while the sum is 31.

The square root of 21198613 is about 4604.1951522497. The cubic root of 21198613 is about 276.7594648465.

The spelling of 21198613 in words is "twenty-one million, one hundred ninety-eight thousand, six hundred thirteen".