21069486 has 48 divisors (see below), whose sum is σ = 47698560. Its totient is φ = 6713280.

The previous prime is 21069439. The next prime is 21069487. The reversal of 21069486 is 68496012.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 21069486.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21069487) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 94371 + ... + 94593.

It is an arithmetic number, because the mean of its divisors is an integer number (993720).

Almost surely, 2^21069486 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21069486, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23849280).

21069486 is an abundant number, since it is smaller than the sum of its proper divisors (26629074).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21069486 is a wasteful number, since it uses less digits than its factorization.

21069486 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 441 (or 438 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 21069486 is about 4590.1509779091. The cubic root of 21069486 is about 276.1963788284.

It can be divided in two parts, 210 and 69486, that added together give a palindrome (69696).

The spelling of 21069486 in words is "twenty-one million, sixty-nine thousand, four hundred eighty-six".