21481412 has 6 divisors (see below), whose sum is σ = 37592478. Its totient is φ = 10740704.

The previous prime is 21481409. The next prime is 21481459. The reversal of 21481412 is 21418412.

It can be written as a sum of positive squares in only one way, i.e., 13719616 + 7761796 = 3704^2 + 2786^2 .

It is a super-2 number, since 2×21481412² = 922902123027488, which contains 22 as substring.

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 as a sum of consecutive naturals, namely, 2685173 + ... + 2685180.

It is an arithmetic number, because the mean of its divisors is an integer number (6265413).

Almost surely, 2^21481412 is an apocalyptic number.

It is an amenable number.

21481412 is a deficient number, since it is larger than the sum of its proper divisors (16111066).

21481412 is a wasteful number, since it uses less digits than its factorization.

21481412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5370357 (or 5370355 counting only the distinct ones).

The product of its digits is 512, while the sum is 23.

The square root of 21481412 is about 4634.8044187430. The cubic root of 21481412 is about 277.9847308005.

Adding to 21481412 its reverse (21418412), we get a palindrome (42899824).

The spelling of 21481412 in words is "twenty-one million, four hundred eighty-one thousand, four hundred twelve".