21210698 has 8 divisors (see below), whose sum is σ = 31855908. Its totient is φ = 10592064.

The previous prime is 21210697. The next prime is 21210703. The reversal of 21210698 is 89601212.

It can be written as a sum of positive squares in 2 ways, for example, as 16703569 + 4507129 = 4087^2 + 2123^2 .

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

It is a self number, because there is not a number n which added to its sum of digits gives 21210698.

It is not an unprimeable number, because it can be changed into a prime (21210691) 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 3 ways as a sum of consecutive naturals, for example, 4511 + ... + 7922.

Almost surely, 2^21210698 is an apocalyptic number.

21210698 is a deficient number, since it is larger than the sum of its proper divisors (10645210).

21210698 is a wasteful number, since it uses less digits than its factorization.

21210698 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13288.

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

The square root of 21210698 is about 4605.5073553301. The cubic root of 21210698 is about 276.8120469464.

The spelling of 21210698 in words is "twenty-one million, two hundred ten thousand, six hundred ninety-eight".