21036774 has 48 divisors (see below), whose sum is σ = 47661120. Its totient is φ = 6138720.

The previous prime is 21036767. The next prime is 21036787. The reversal of 21036774 is 47763012.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 55317 + ... + 55695.

It is an arithmetic number, because the mean of its divisors is an integer number (992940).

Almost surely, 2^21036774 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21036774, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23830560).

21036774 is an abundant number, since it is smaller than the sum of its proper divisors (26624346).

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

21036774 is a wasteful number, since it uses less digits than its factorization.

21036774 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 453 (or 424 counting only the distinct ones).

The product of its (nonzero) digits is 7056, while the sum is 30.

The square root of 21036774 is about 4586.5863122806. The cubic root of 21036774 is about 276.0533660722.

Adding to 21036774 its reverse (47763012), we get a palindrome (68799786).

The spelling of 21036774 in words is "twenty-one million, thirty-six thousand, seven hundred seventy-four".