21008635198 has 8 divisors (see below), whose sum is σ = 33171529320. Its totient is φ = 9951458760.

The previous prime is 21008635177. The next prime is 21008635199. The reversal of 21008635198 is 89153680012.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21008635199) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 276429373 + ... + 276429448.

It is an arithmetic number, because the mean of its divisors is an integer number (4146441165).

Almost surely, 2^21008635198 is an apocalyptic number.

21008635198 is a deficient number, since it is larger than the sum of its proper divisors (12162894122).

21008635198 is a wasteful number, since it uses less digits than its factorization.

21008635198 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 552858842.

The product of its (nonzero) digits is 103680, while the sum is 43.

The spelling of 21008635198 in words is "twenty-one billion, eight million, six hundred thirty-five thousand, one hundred ninety-eight".