21053783 has 2 divisors, whose sum is σ = 21053784. Its totient is φ = 21053782.

The previous prime is 21053741. The next prime is 21053831. The reversal of 21053783 is 38735012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21053783 - 2²⁰ = 20005207 is a prime.

It is a super-2 number, since 2×21053783² = 886523557222178, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21053713) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10526891 + 10526892.

It is an arithmetic number, because the mean of its divisors is an integer number (10526892).

Almost surely, 2^21053783 is an apocalyptic number.

21053783 is a deficient number, since it is larger than the sum of its proper divisors (1).

21053783 is an equidigital number, since it uses as much as digits as its factorization.

21053783 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5040, while the sum is 29.

The square root of 21053783 is about 4588.4401488959. The cubic root of 21053783 is about 276.1277457721.

Adding to 21053783 its reverse (38735012), we get a palindrome (59788795).

The spelling of 21053783 in words is "twenty-one million, fifty-three thousand, seven hundred eighty-three".