21322375 has 8 divisors (see below), whose sum is σ = 26610480. Its totient is φ = 17057800.

The previous prime is 21322361. The next prime is 21322381. The reversal of 21322375 is 57322312.

It is not a de Polignac number, because 21322375 - 2²¹ = 19225223 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 85165 + ... + 85414.

It is an arithmetic number, because the mean of its divisors is an integer number (3326310).

Almost surely, 2^21322375 is an apocalyptic number.

21322375 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21322375 is a deficient number, since it is larger than the sum of its proper divisors (5288105).

21322375 is an equidigital number, since it uses as much as digits as its factorization.

21322375 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 170594 (or 170584 counting only the distinct ones).

The product of its digits is 2520, while the sum is 25.

The square root of 21322375 is about 4617.6157267577. The cubic root of 21322375 is about 277.2970135821.

Adding to 21322375 its reverse (57322312), we get a palindrome (78644687).

The spelling of 21322375 in words is "twenty-one million, three hundred twenty-two thousand, three hundred seventy-five".