21372198 has 16 divisors (see below), whose sum is σ = 44603136. Its totient is φ = 6814280.

The previous prime is 21372187. The next prime is 21372227. The reversal of 21372198 is 89127312.

It is a congruent number.

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, 77298 + ... + 77573.

It is an arithmetic number, because the mean of its divisors is an integer number (2787696).

Almost surely, 2^21372198 is an apocalyptic number.

21372198 is an abundant number, since it is smaller than the sum of its proper divisors (23230938).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21372198 is a wasteful number, since it uses less digits than its factorization.

21372198 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 154899.

The product of its digits is 6048, while the sum is 33.

The square root of 21372198 is about 4623.0074626805. The cubic root of 21372198 is about 277.5128279112.

The spelling of 21372198 in words is "twenty-one million, three hundred seventy-two thousand, one hundred ninety-eight".