21344345 has 32 divisors (see below), whose sum is σ = 29859840. Its totient is φ = 14491840.

The previous prime is 21344339. The next prime is 21344347. The reversal of 21344345 is 54344312.

It is not a de Polignac number, because 21344345 - 2¹⁴ = 21327961 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21344347) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 59276 + ... + 59634.

It is an arithmetic number, because the mean of its divisors is an integer number (933120).

Almost surely, 2^21344345 is an apocalyptic number.

It is an amenable number.

21344345 is a deficient number, since it is larger than the sum of its proper divisors (8515495).

21344345 is a wasteful number, since it uses less digits than its factorization.

21344345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 445.

The product of its digits is 5760, while the sum is 26.

The square root of 21344345 is about 4619.9940476152. The cubic root of 21344345 is about 277.3922206774.

Adding to 21344345 its reverse (54344312), we get a palindrome (75688657).

The spelling of 21344345 in words is "twenty-one million, three hundred forty-four thousand, three hundred forty-five".