21352743 has 12 divisors (see below), whose sum is σ = 31051800. Its totient is φ = 14138736.

The previous prime is 21352733. The next prime is 21352781. The reversal of 21352743 is 34725312.

It is not a de Polignac number, because 21352743 - 2¹⁰ = 21351719 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21352703) 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, 6621 + ... + 9302.

It is an arithmetic number, because the mean of its divisors is an integer number (2587650).

Almost surely, 2^21352743 is an apocalyptic number.

21352743 is a deficient number, since it is larger than the sum of its proper divisors (9699057).

21352743 is a wasteful number, since it uses less digits than its factorization.

21352743 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16078 (or 16075 counting only the distinct ones).

The product of its digits is 5040, while the sum is 27.

The square root of 21352743 is about 4620.9028338627. The cubic root of 21352743 is about 277.4285961891.

The spelling of 21352743 in words is "twenty-one million, three hundred fifty-two thousand, seven hundred forty-three".