21136526 has 4 divisors (see below), whose sum is σ = 31704792. Its totient is φ = 10568262.

The previous prime is 21136523. The next prime is 21136541. The reversal of 21136526 is 62563112.

It is a semiprime because it is the product of two primes.

It is a junction number, because it is equal to n+sod(n) for n = 21136495 and 21136504.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21136523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5284130 + ... + 5284133.

It is an arithmetic number, because the mean of its divisors is an integer number (7926198).

Almost surely, 2^21136526 is an apocalyptic number.

21136526 is a deficient number, since it is larger than the sum of its proper divisors (10568266).

21136526 is a wasteful number, since it uses less digits than its factorization.

21136526 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10568265.

The product of its digits is 2160, while the sum is 26.

The square root of 21136526 is about 4597.4477702308. The cubic root of 21136526 is about 276.4890074077.

Adding to 21136526 its reverse (62563112), we get a palindrome (83699638).

The spelling of 21136526 in words is "twenty-one million, one hundred thirty-six thousand, five hundred twenty-six".