21025359 has 8 divisors (see below), whose sum is σ = 31148720. Its totient is φ = 14016888.

The previous prime is 21025357. The next prime is 21025363. The reversal of 21025359 is 95352012.

It is not a de Polignac number, because 21025359 - 2¹ = 21025357 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 778717 = 21025359 / (2 + 1 + 0 + 2 + 5 + 3 + 5 + 9).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21025351) 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, 389332 + ... + 389385.

It is an arithmetic number, because the mean of its divisors is an integer number (3893590).

Almost surely, 2^21025359 is an apocalyptic number.

21025359 is a deficient number, since it is larger than the sum of its proper divisors (10123361).

21025359 is an equidigital number, since it uses as much as digits as its factorization.

21025359 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 778726 (or 778720 counting only the distinct ones).

The product of its (nonzero) digits is 2700, while the sum is 27.

The square root of 21025359 is about 4585.3417538936. The cubic root of 21025359 is about 276.0034262335.

The spelling of 21025359 in words is "twenty-one million, twenty-five thousand, three hundred fifty-nine".