21059395 has 8 divisors (see below), whose sum is σ = 28881504. Its totient is φ = 14440704.

The previous prime is 21059393. The next prime is 21059399. The reversal of 21059395 is 59395012.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21059395 - 2¹ = 21059393 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21059395.

It is not an unprimeable number, because it can be changed into a prime (21059393) 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 7 ways as a sum of consecutive naturals, for example, 300814 + ... + 300883.

It is an arithmetic number, because the mean of its divisors is an integer number (3610188).

Almost surely, 2^21059395 is an apocalyptic number.

21059395 is a deficient number, since it is larger than the sum of its proper divisors (7822109).

21059395 is an equidigital number, since it uses as much as digits as its factorization.

21059395 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 601709.

The product of its (nonzero) digits is 12150, while the sum is 34.

The square root of 21059395 is about 4589.0516449480. The cubic root of 21059395 is about 276.1522780417.

The spelling of 21059395 in words is "twenty-one million, fifty-nine thousand, three hundred ninety-five".