21081074 has 24 divisors (see below), whose sum is σ = 37213020. Its totient is φ = 8929536.

The previous prime is 21081061. The next prime is 21081101. The reversal of 21081074 is 47018012.

It can be written as a sum of positive squares in 2 ways, for example, as 20638849 + 442225 = 4543^2 + 665^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7514 + ... + 9930.

Almost surely, 2^21081074 is an apocalyptic number.

21081074 is a deficient number, since it is larger than the sum of its proper divisors (16131946).

21081074 is a wasteful number, since it uses less digits than its factorization.

21081074 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2522 (or 2515 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 23.

The square root of 21081074 is about 4591.4130722469. The cubic root of 21081074 is about 276.2470046016.

Adding to 21081074 its reverse (47018012), we get a palindrome (68099086).

The spelling of 21081074 in words is "twenty-one million, eighty-one thousand, seventy-four".