21146774 has 32 divisors (see below), whose sum is σ = 36191232. Its totient is φ = 9180000.

The previous prime is 21146747. The next prime is 21146779. The reversal of 21146774 is 47764112.

It is a self number, because there is not a number n which added to its sum of digits gives 21146774.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21146779) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 68729 + ... + 69035.

It is an arithmetic number, because the mean of its divisors is an integer number (1130976).

Almost surely, 2^21146774 is an apocalyptic number.

21146774 is a deficient number, since it is larger than the sum of its proper divisors (15044458).

21146774 is a wasteful number, since it uses less digits than its factorization.

21146774 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 452.

The product of its digits is 9408, while the sum is 32.

The square root of 21146774 is about 4598.5621665908. The cubic root of 21146774 is about 276.5336852250.

It can be divided in two parts, 2114 and 6774, that added together give a palindrome (8888).

The spelling of 21146774 in words is "twenty-one million, one hundred forty-six thousand, seven hundred seventy-four".