21445007 has 8 divisors (see below), whose sum is σ = 23490000. Its totient is φ = 19487104.

The previous prime is 21444979. The next prime is 21445013. The reversal of 21445007 is 70054412.

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 21445007 - 2⁸ = 21444751 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21445037) 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, 21257 + ... + 22242.

It is an arithmetic number, because the mean of its divisors is an integer number (2936250).

Almost surely, 2^21445007 is an apocalyptic number.

21445007 is a deficient number, since it is larger than the sum of its proper divisors (2044993).

21445007 is a wasteful number, since it uses less digits than its factorization.

21445007 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43545.

The product of its (nonzero) digits is 1120, while the sum is 23.

The square root of 21445007 is about 4630.8754032040. The cubic root of 21445007 is about 277.8276064862.

Adding to 21445007 its reverse (70054412), we get a palindrome (91499419).

The spelling of 21445007 in words is "twenty-one million, four hundred forty-five thousand, seven".