21336145 has 8 divisors (see below), whose sum is σ = 26951040. Its totient is φ = 16170480.

The previous prime is 21336137. The next prime is 21336151. The reversal of 21336145 is 54163312.

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

It is not a de Polignac number, because 21336145 - 2³ = 21336137 is a prime.

It is a super-2 number, since 2×21336145² = 910462166922050, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 112201 + ... + 112390.

It is an arithmetic number, because the mean of its divisors is an integer number (3368880).

Almost surely, 2^21336145 is an apocalyptic number.

It is an amenable number.

21336145 is a deficient number, since it is larger than the sum of its proper divisors (5614895).

21336145 is a wasteful number, since it uses less digits than its factorization.

21336145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 224615.

The product of its digits is 2160, while the sum is 25.

The square root of 21336145 is about 4619.1065153339. The cubic root of 21336145 is about 277.3566935849.

Adding to 21336145 its reverse (54163312), we get a palindrome (75499457).

The spelling of 21336145 in words is "twenty-one million, three hundred thirty-six thousand, one hundred forty-five".