21527051 has 24 divisors (see below), whose sum is σ = 27546624. Its totient is φ = 16454880.

The previous prime is 21527029. The next prime is 21527059. The reversal of 21527051 is 15072512.

It is a happy number.

It is not a de Polignac number, because 21527051 - 2¹⁰ = 21526027 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21527059) 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 23 ways as a sum of consecutive naturals, for example, 36380 + ... + 36966.

It is an arithmetic number, because the mean of its divisors is an integer number (1147776).

Almost surely, 2^21527051 is an apocalyptic number.

21527051 is a deficient number, since it is larger than the sum of its proper divisors (6019573).

21527051 is a wasteful number, since it uses less digits than its factorization.

21527051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 651 (or 638 counting only the distinct ones).

The product of its (nonzero) digits is 700, while the sum is 23.

The square root of 21527051 is about 4639.7253151453. The cubic root of 21527051 is about 278.1814585715.

Adding to 21527051 its reverse (15072512), we get a palindrome (36599563).

The spelling of 21527051 in words is "twenty-one million, five hundred twenty-seven thousand, fifty-one".