21905343 has 16 divisors (see below), whose sum is σ = 33004800. Its totient is φ = 14355000.

The previous prime is 21905339. The next prime is 21905383. The reversal of 21905343 is 34350912.

It is not a de Polignac number, because 21905343 - 2² = 21905339 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21905383) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5283 + ... + 8468.

It is an arithmetic number, because the mean of its divisors is an integer number (2062800).

Almost surely, 2^21905343 is an apocalyptic number.

21905343 is a deficient number, since it is larger than the sum of its proper divisors (11099457).

21905343 is a wasteful number, since it uses less digits than its factorization.

21905343 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13819 (or 13813 counting only the distinct ones).

The product of its (nonzero) digits is 3240, while the sum is 27.

The square root of 21905343 is about 4680.3144125155. The cubic root of 21905343 is about 279.8014876949.

The spelling of 21905343 in words is "twenty-one million, nine hundred five thousand, three hundred forty-three".