21162743 has 8 divisors (see below), whose sum is σ = 24224640. Its totient is φ = 18110520.

The previous prime is 21162727. The next prime is 21162749. The reversal of 21162743 is 34726112.

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

It is a cyclic number.

It is not a de Polignac number, because 21162743 - 2⁴ = 21162727 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21162749) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3128 + ... + 7218.

It is an arithmetic number, because the mean of its divisors is an integer number (3028080).

Almost surely, 2^21162743 is an apocalyptic number.

21162743 is a deficient number, since it is larger than the sum of its proper divisors (3061897).

21162743 is an equidigital number, since it uses as much as digits as its factorization.

21162743 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4837.

The product of its digits is 2016, while the sum is 26.

The square root of 21162743 is about 4600.2981425121. The cubic root of 21162743 is about 276.6032759076.

Adding to 21162743 its reverse (34726112), we get a palindrome (55888855).

The spelling of 21162743 in words is "twenty-one million, one hundred sixty-two thousand, seven hundred forty-three".