21142021443 has 4 divisors (see below), whose sum is σ = 28189361928. Its totient is φ = 14094680960.

The previous prime is 21142021441. The next prime is 21142021451. The reversal of 21142021443 is 34412024112.

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 21142021443 - 2¹ = 21142021441 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21142021441) 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, 3523670238 + ... + 3523670243.

It is an arithmetic number, because the mean of its divisors is an integer number (7047340482).

Almost surely, 2^21142021443 is an apocalyptic number.

21142021443 is a deficient number, since it is larger than the sum of its proper divisors (7047340485).

21142021443 is an equidigital number, since it uses as much as digits as its factorization.

21142021443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7047340484.

The product of its (nonzero) digits is 1536, while the sum is 24.

Adding to 21142021443 its reverse (34412024112), we get a palindrome (55554045555).

The spelling of 21142021443 in words is "twenty-one billion, one hundred forty-two million, twenty-one thousand, four hundred forty-three".