21335385 has 16 divisors (see below), whose sum is σ = 35933760. Its totient is φ = 10779840.

The previous prime is 21335359. The next prime is 21335389. The reversal of 21335385 is 58353312.

It is not a de Polignac number, because 21335385 - 2⁷ = 21335257 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21335389) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 37146 + ... + 37715.

It is an arithmetic number, because the mean of its divisors is an integer number (2245860).

Almost surely, 2^21335385 is an apocalyptic number.

It is an amenable number.

21335385 is a deficient number, since it is larger than the sum of its proper divisors (14598375).

21335385 is a wasteful number, since it uses less digits than its factorization.

21335385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74888.

The product of its digits is 10800, while the sum is 30.

The square root of 21335385 is about 4619.0242476090. The cubic root of 21335385 is about 277.3534003691.

Adding to 21335385 its reverse (58353312), we get a palindrome (79688697).

The spelling of 21335385 in words is "twenty-one million, three hundred thirty-five thousand, three hundred eighty-five".