21364441 has 16 divisors (see below), whose sum is σ = 25120000. Its totient is φ = 18162144.

The previous prime is 21364433. The next prime is 21364451. The reversal of 21364441 is 14446312.

It is not a de Polignac number, because 21364441 - 2³ = 21364433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21364411) 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, 68101 + ... + 68413.

It is an arithmetic number, because the mean of its divisors is an integer number (1570000).

Almost surely, 2^21364441 is an apocalyptic number.

It is an amenable number.

21364441 is a deficient number, since it is larger than the sum of its proper divisors (3755559).

21364441 is an equidigital number, since it uses as much as digits as its factorization.

21364441 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 533 (or 519 counting only the distinct ones).

The product of its digits is 2304, while the sum is 25.

The square root of 21364441 is about 4622.1684305096. The cubic root of 21364441 is about 277.4792495914.

The spelling of 21364441 in words is "twenty-one million, three hundred sixty-four thousand, four hundred forty-one".