21304146 has 8 divisors (see below), whose sum is σ = 42608304. Its totient is φ = 7101380.

The previous prime is 21304139. The next prime is 21304147. The reversal of 21304146 is 64140312.

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

21304146 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (21304147) 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, 1775340 + ... + 1775351.

It is an arithmetic number, because the mean of its divisors is an integer number (5326038).

Almost surely, 2^21304146 is an apocalyptic number.

21304146 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.

21304146 is a wasteful number, since it uses less digits than its factorization.

21304146 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3550696.

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 21304146 is about 4615.6414505462. The cubic root of 21304146 is about 277.2179684718.

Adding to 21304146 its reverse (64140312), we get a palindrome (85444458).

The spelling of 21304146 in words is "twenty-one million, three hundred four thousand, one hundred forty-six".