21356698 has 16 divisors (see below), whose sum is σ = 35019360. Its totient is φ = 9687600.

The previous prime is 21356689. The next prime is 21356711. The reversal of 21356698 is 89665312.

It is a super-2 number, since 2×21356698² = 912217098926408, which contains 22 as substring.

It is a plaindrome in base 13.

It is a self number, because there is not a number n which added to its sum of digits gives 21356698.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 17653 + ... + 18823.

It is an arithmetic number, because the mean of its divisors is an integer number (2188710).

Almost surely, 2^21356698 is an apocalyptic number.

21356698 is a deficient number, since it is larger than the sum of its proper divisors (13662662).

21356698 is a wasteful number, since it uses less digits than its factorization.

21356698 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2013.

The product of its digits is 77760, while the sum is 40.

The square root of 21356698 is about 4621.3307607225. The cubic root of 21356698 is about 277.4457237678.

The spelling of 21356698 in words is "twenty-one million, three hundred fifty-six thousand, six hundred ninety-eight".