21344807 has 4 divisors (see below), whose sum is σ = 23285256. Its totient is φ = 19404360.

The previous prime is 21344803. The next prime is 21344821. The reversal of 21344807 is 70844312.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21344807 - 2² = 21344803 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21344807.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21344803) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 970208 + ... + 970229.

It is an arithmetic number, because the mean of its divisors is an integer number (5821314).

Almost surely, 2^21344807 is an apocalyptic number.

21344807 is a deficient number, since it is larger than the sum of its proper divisors (1940449).

21344807 is a wasteful number, since it uses less digits than its factorization.

21344807 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1940448.

The product of its (nonzero) digits is 5376, while the sum is 29.

The square root of 21344807 is about 4620.0440474091. The cubic root of 21344807 is about 277.3942220550.

The spelling of 21344807 in words is "twenty-one million, three hundred forty-four thousand, eight hundred seven".