21004358 has 4 divisors (see below), whose sum is σ = 31506540. Its totient is φ = 10502178.

The previous prime is 21004351. The next prime is 21004387. The reversal of 21004358 is 85340012.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21004351) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5251088 + ... + 5251091.

It is an arithmetic number, because the mean of its divisors is an integer number (7876635).

Almost surely, 2^21004358 is an apocalyptic number.

21004358 is a deficient number, since it is larger than the sum of its proper divisors (10502182).

21004358 is a wasteful number, since it uses less digits than its factorization.

21004358 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10502181.

The product of its (nonzero) digits is 960, while the sum is 23.

The square root of 21004358 is about 4583.0511670720. The cubic root of 21004358 is about 275.9115010666.

The spelling of 21004358 in words is "twenty-one million, four thousand, three hundred fifty-eight".