21329998 has 8 divisors (see below), whose sum is σ = 32174280. Its totient is φ = 10605240.

The previous prime is 21329983. The next prime is 21329999. The reversal of 21329998 is 89992312.

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 (21329999) 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, 29433 + ... + 30148.

It is an arithmetic number, because the mean of its divisors is an integer number (4021785).

Almost surely, 2^21329998 is an apocalyptic number.

21329998 is a deficient number, since it is larger than the sum of its proper divisors (10844282).

21329998 is a wasteful number, since it uses less digits than its factorization.

21329998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59762.

The product of its digits is 69984, while the sum is 43.

The square root of 21329998 is about 4618.4410789789. The cubic root of 21329998 is about 277.3300552934.

The spelling of 21329998 in words is "twenty-one million, three hundred twenty-nine thousand, nine hundred ninety-eight".