21070384 has 10 divisors (see below), whose sum is σ = 40823900. Its totient is φ = 10535184.

The previous prime is 21070363. The next prime is 21070393. The reversal of 21070384 is 48307012.

It is a super-2 number, since 2×21070384² = 887922163814912, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 658434 + ... + 658465.

It is an arithmetic number, because the mean of its divisors is an integer number (4082390).

Almost surely, 2^21070384 is an apocalyptic number.

It is an amenable number.

21070384 is a deficient number, since it is larger than the sum of its proper divisors (19753516).

21070384 is a wasteful number, since it uses less digits than its factorization.

21070384 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1316907 (or 1316901 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 25.

The square root of 21070384 is about 4590.2487950001. The cubic root of 21070384 is about 276.2003026834.

Adding to 21070384 its reverse (48307012), we get a palindrome (69377396).

The spelling of 21070384 in words is "twenty-one million, seventy thousand, three hundred eighty-four".