21300218 has 8 divisors (see below), whose sum is σ = 33829812. Its totient is φ = 10023616.

The previous prime is 21300203. The next prime is 21300233. The reversal of 21300218 is 81200312.

It is an interprime number because it is at equal distance from previous prime (21300203) and next prime (21300233).

It can be written as a sum of positive squares in 2 ways, for example, as 21279769 + 20449 = 4613^2 + 143^2 .

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

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a junction number, because it is equal to n+sod(n) for n = 21300196 and 21300205.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 313205 + ... + 313272.

Almost surely, 2^21300218 is an apocalyptic number.

21300218 is a deficient number, since it is larger than the sum of its proper divisors (12529594).

21300218 is a wasteful number, since it uses less digits than its factorization.

21300218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 626496.

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 21300218 is about 4615.2159212761. The cubic root of 21300218 is about 277.2009298617.

The spelling of 21300218 in words is "twenty-one million, three hundred thousand, two hundred eighteen".