21525369 has 8 divisors (see below), whose sum is σ = 29400672. Its totient is φ = 14000160.

The previous prime is 21525359. The next prime is 21525373. The reversal of 21525369 is 96352512.

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

It is not a de Polignac number, because 21525369 - 2⁴ = 21525353 is a prime.

It is a super-2 number, since 2×21525369² = 926683021172322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21525319) 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 7 ways as a sum of consecutive naturals, for example, 87379 + ... + 87624.

It is an arithmetic number, because the mean of its divisors is an integer number (3675084).

Almost surely, 2^21525369 is an apocalyptic number.

It is an amenable number.

21525369 is a deficient number, since it is larger than the sum of its proper divisors (7875303).

21525369 is a wasteful number, since it uses less digits than its factorization.

21525369 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 175047.

The product of its digits is 16200, while the sum is 33.

The square root of 21525369 is about 4639.5440508740. The cubic root of 21525369 is about 278.1742132162.

The spelling of 21525369 in words is "twenty-one million, five hundred twenty-five thousand, three hundred sixty-nine".