21083737 has 4 divisors (see below), whose sum is σ = 21093300. Its totient is φ = 21074176.

The previous prime is 21083719. The next prime is 21083773. The reversal of 21083737 is 73738012.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 4076361 + 17007376 = 2019^2 + 4124^2 .

It is a cyclic number.

It is not a de Polignac number, because 21083737 - 2¹⁵ = 21050969 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21083699 and 21083708.

It is not an unprimeable number, because it can be changed into a prime (21083537) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 393 + ... + 6505.

It is an arithmetic number, because the mean of its divisors is an integer number (5273325).

Almost surely, 2^21083737 is an apocalyptic number.

It is an amenable number.

21083737 is a deficient number, since it is larger than the sum of its proper divisors (9563).

21083737 is an equidigital number, since it uses as much as digits as its factorization.

21083737 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9562.

The product of its (nonzero) digits is 7056, while the sum is 31.

The square root of 21083737 is about 4591.7030609568. The cubic root of 21083737 is about 276.2586361216.

The spelling of 21083737 in words is "twenty-one million, eighty-three thousand, seven hundred thirty-seven".