21385595 has 16 divisors (see below), whose sum is σ = 31995648. Its totient is φ = 13331040.

The previous prime is 21385591. The next prime is 21385597. The reversal of 21385595 is 59558312.

It is not a de Polignac number, because 21385595 - 2² = 21385591 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21385591) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27389 + ... + 28158.

It is an arithmetic number, because the mean of its divisors is an integer number (1999728).

Almost surely, 2^21385595 is an apocalyptic number.

21385595 is a deficient number, since it is larger than the sum of its proper divisors (10610053).

21385595 is a wasteful number, since it uses less digits than its factorization.

21385595 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55570.

The product of its digits is 54000, while the sum is 38.

The square root of 21385595 is about 4624.4561842448. The cubic root of 21385595 is about 277.5708014023.

The spelling of 21385595 in words is "twenty-one million, three hundred eighty-five thousand, five hundred ninety-five".