21052783 has 12 divisors (see below), whose sum is σ = 22624672. Its totient is φ = 19584000.

The previous prime is 21052771. The next prime is 21052841. The reversal of 21052783 is 38725012.

It is not a de Polignac number, because 21052783 - 2¹⁷ = 20921711 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21052483) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 27658 + ... + 28408.

Almost surely, 2^21052783 is an apocalyptic number.

21052783 is a deficient number, since it is larger than the sum of its proper divisors (1571889).

21052783 is an equidigital number, since it uses as much as digits as its factorization.

21052783 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 882 (or 865 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 28.

The square root of 21052783 is about 4588.3311781082. The cubic root of 21052783 is about 276.1233739193.

Adding to 21052783 its reverse (38725012), we get a palindrome (59777795).

The spelling of 21052783 in words is "twenty-one million, fifty-two thousand, seven hundred eighty-three".