21004354 has 24 divisors (see below), whose sum is σ = 36713088. Its totient is φ = 8828760.

The previous prime is 21004351. The next prime is 21004387. The reversal of 21004354 is 45340012.

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

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 48519 + ... + 48949.

It is an arithmetic number, because the mean of its divisors is an integer number (1529712).

Almost surely, 2^21004354 is an apocalyptic number.

21004354 is a deficient number, since it is larger than the sum of its proper divisors (15708734).

21004354 is an equidigital number, since it uses as much as digits as its factorization.

21004354 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 558 (or 499 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 19.

The square root of 21004354 is about 4583.0507306815. The cubic root of 21004354 is about 275.9114835520.

Adding to 21004354 its reverse (45340012), we get a palindrome (66344366).

The spelling of 21004354 in words is "twenty-one million, four thousand, three hundred fifty-four".