21106525 has 48 divisors (see below), whose sum is σ = 30855168. Its totient is φ = 14168000.

The previous prime is 21106523. The next prime is 21106531. The reversal of 21106525 is 52560112.

It is not a de Polignac number, because 21106525 - 2¹ = 21106523 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21106496 and 21106505.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21106523) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 297240 + ... + 297310.

It is an arithmetic number, because the mean of its divisors is an integer number (642816).

Almost surely, 2^21106525 is an apocalyptic number.

21106525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21106525 is a deficient number, since it is larger than the sum of its proper divisors (9748643).

21106525 is a wasteful number, since it uses less digits than its factorization.

21106525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162 (or 157 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 22.

The square root of 21106525 is about 4594.1838230528. The cubic root of 21106525 is about 276.3581301072.

Adding to 21106525 its reverse (52560112), we get a palindrome (73666637).

The spelling of 21106525 in words is "twenty-one million, one hundred six thousand, five hundred twenty-five".