21486536 has 8 divisors (see below), whose sum is σ = 40287270. Its totient is φ = 10743264.

The previous prime is 21486527. The next prime is 21486539. The reversal of 21486536 is 63568412.

It can be written as a sum of positive squares in only one way, i.e., 18576100 + 2910436 = 4310^2 + 1706^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a junction number, because it is equal to n+sod(n) for n = 21486496 and 21486505.

It is not an unprimeable number, because it can be changed into a prime (21486539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1342901 + ... + 1342916.

Almost surely, 2^21486536 is an apocalyptic number.

It is an amenable number.

21486536 is a deficient number, since it is larger than the sum of its proper divisors (18800734).

21486536 is a wasteful number, since it uses less digits than its factorization.

21486536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2685823 (or 2685819 counting only the distinct ones).

The product of its digits is 34560, while the sum is 35.

The square root of 21486536 is about 4635.3571599177. The cubic root of 21486536 is about 278.0068317766.

It can be divided in two parts, 21486 and 536, that added together give a palindrome (22022).

The spelling of 21486536 in words is "twenty-one million, four hundred eighty-six thousand, five hundred thirty-six".