21738562 has 8 divisors (see below), whose sum is σ = 32924736. Its totient is φ = 10763652.

The previous prime is 21738551. The next prime is 21738571. The reversal of 21738562 is 26583712.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 52558 + ... + 52969.

It is an arithmetic number, because the mean of its divisors is an integer number (4115592).

Almost surely, 2^21738562 is an apocalyptic number.

21738562 is a deficient number, since it is larger than the sum of its proper divisors (11186174).

21738562 is a wasteful number, since it uses less digits than its factorization.

21738562 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105632.

The product of its digits is 20160, while the sum is 34.

The square root of 21738562 is about 4662.4630829638. The cubic root of 21738562 is about 279.0895684127.

The spelling of 21738562 in words is "twenty-one million, seven hundred thirty-eight thousand, five hundred sixty-two".