21337628 has 12 divisors (see below), whose sum is σ = 40213320. Its totient is φ = 9848112.

The previous prime is 21337621. The next prime is 21337633. The reversal of 21337628 is 82673312.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21337594 and 21337603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21337621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 205118 + ... + 205221.

It is an arithmetic number, because the mean of its divisors is an integer number (3351110).

Almost surely, 2^21337628 is an apocalyptic number.

It is an amenable number.

21337628 is a deficient number, since it is larger than the sum of its proper divisors (18875692).

21337628 is a wasteful number, since it uses less digits than its factorization.

21337628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 410356 (or 410354 counting only the distinct ones).

The product of its digits is 12096, while the sum is 32.

The square root of 21337628 is about 4619.2670414255. The cubic root of 21337628 is about 277.3631194637.

The spelling of 21337628 in words is "twenty-one million, three hundred thirty-seven thousand, six hundred twenty-eight".