21325275 has 30 divisors (see below), whose sum is σ = 39505532. Its totient is φ = 11372400.

The previous prime is 21325219. The next prime is 21325279. The reversal of 21325275 is 57252312.

21325275 is a `hidden beast` number, since 2 + 132 + 527 + 5 = 666.

It is not a de Polignac number, because 21325275 - 2⁷ = 21325147 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21325279) by changing a digit.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 3241 + ... + 7290.

Almost surely, 2^21325275 is an apocalyptic number.

21325275 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21325275 is a deficient number, since it is larger than the sum of its proper divisors (18180257).

21325275 is a wasteful number, since it uses less digits than its factorization.

21325275 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10553 (or 10539 counting only the distinct ones).

The product of its digits is 4200, while the sum is 27.

The square root of 21325275 is about 4617.9297309509. The cubic root of 21325275 is about 277.3095844907.

Adding to 21325275 its reverse (57252312), we get a palindrome (78577587).

The spelling of 21325275 in words is "twenty-one million, three hundred twenty-five thousand, two hundred seventy-five".