21421330443 has 16 divisors (see below), whose sum is σ = 32829626400. Its totient is φ = 13788442080.

The previous prime is 21421330433. The next prime is 21421330457. The reversal of 21421330443 is 34403312412.

21421330443 is a `hidden beast` number, since 2 + 1 + 4 + 213 + 3 + 0 + 443 = 666.

It is not a de Polignac number, because 21421330443 - 2³⁰ = 20347588619 is a prime.

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

It is not an unprimeable number, because it can be changed into a prime (21421330433) 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, 13678228 + ... + 13679793.

It is an arithmetic number, because the mean of its divisors is an integer number (2051851650).

Almost surely, 2^21421330443 is an apocalyptic number.

21421330443 is a deficient number, since it is larger than the sum of its proper divisors (11408295957).

21421330443 is a wasteful number, since it uses less digits than its factorization.

21421330443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27358059 (or 27358053 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 27.

Adding to 21421330443 its reverse (34403312412), we get a palindrome (55824642855).

The spelling of 21421330443 in words is "twenty-one billion, four hundred twenty-one million, three hundred thirty thousand, four hundred forty-three".