21082743 has 48 divisors (see below), whose sum is σ = 35582976. Its totient is φ = 11901120.

The previous prime is 21082729. The next prime is 21082757. The reversal of 21082743 is 34728012.

It is an interprime number because it is at equal distance from previous prime (21082729) and next prime (21082757).

It is not a de Polignac number, because 21082743 - 2¹⁴ = 21066359 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21082783) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 106921 + ... + 107117.

It is an arithmetic number, because the mean of its divisors is an integer number (741312).

Almost surely, 2^21082743 is an apocalyptic number.

21082743 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

21082743 is a deficient number, since it is larger than the sum of its proper divisors (14500233).

21082743 is a wasteful number, since it uses less digits than its factorization.

21082743 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 284 (or 281 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 21082743 is about 4591.5948209745. The cubic root of 21082743 is about 276.2542946173.

It can be divided in two parts, 2108 and 2743, that added together give a triangular number (4851 = T₉₈).

The spelling of 21082743 in words is "twenty-one million, eighty-two thousand, seven hundred forty-three".