21012343 has 8 divisors (see below), whose sum is σ = 23150736. Its totient is φ = 18912000.

The previous prime is 21012331. The next prime is 21012349. The reversal of 21012343 is 34321012.

It is a happy number.

21012343 is an esthetic number in base 10, because in such base its adjacent digits differ by 1.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21012343 - 2⁵ = 21012311 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 (21012349) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8346 + ... + 10567.

It is an arithmetic number, because the mean of its divisors is an integer number (2893842).

Almost surely, 2^21012343 is an apocalyptic number.

21012343 is a deficient number, since it is larger than the sum of its proper divisors (2138393).

21012343 is a wasteful number, since it uses less digits than its factorization.

21012343 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19025.

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 21012343 is about 4583.9222288342. The cubic root of 21012343 is about 275.9464600691.

Adding to 21012343 its reverse (34321012), we get a palindrome (55333355).

It can be divided in two parts, 2101 and 2343, that added together give a palindrome (4444).

The spelling of 21012343 in words is "twenty-one million, twelve thousand, three hundred forty-three".