21001336 has 16 divisors (see below), whose sum is σ = 40735800. Its totient is φ = 10138464.

The previous prime is 21001319. The next prime is 21001349. The reversal of 21001336 is 63310012.

It is a super-2 number, since 2×21001336² = 882112227569792, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 45030 + ... + 45493.

Almost surely, 2^21001336 is an apocalyptic number.

It is an amenable number.

21001336 is a deficient number, since it is larger than the sum of its proper divisors (19734464).

21001336 is a wasteful number, since it uses less digits than its factorization.

21001336 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90558 (or 90554 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 16.

The square root of 21001336 is about 4582.7214621882. The cubic root of 21001336 is about 275.8982681850.

Adding to 21001336 its reverse (63310012), we get a palindrome (84311348).

The spelling of 21001336 in words is "twenty-one million, one thousand, three hundred thirty-six".