21698142 has 8 divisors (see below), whose sum is σ = 43396296. Its totient is φ = 7232712.

The previous prime is 21698107. The next prime is 21698153. The reversal of 21698142 is 24189612.

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

21698142 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1808173 + ... + 1808184.

It is an arithmetic number, because the mean of its divisors is an integer number (5424537).

Almost surely, 2^21698142 is an apocalyptic number.

21698142 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21698142 is a wasteful number, since it uses less digits than its factorization.

21698142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3616362.

The product of its digits is 6912, while the sum is 33.

The square root of 21698142 is about 4658.1264474035. The cubic root of 21698142 is about 278.9164842975.

The spelling of 21698142 in words is "twenty-one million, six hundred ninety-eight thousand, one hundred forty-two".