21411003421 has 4 divisors (see below), whose sum is σ = 21484078812. Its totient is φ = 21337928032.

The previous prime is 21411003407. The next prime is 21411003431. The reversal of 21411003421 is 12430011412.

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

It can be written as a sum of positive squares in 2 ways, for example, as 9242707321 + 12168296100 = 96139^2 + 110310^2 .

It is a cyclic number.

It is not a de Polignac number, because 21411003421 - 2⁷ = 21411003293 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21411003431) 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, 36537256 + ... + 36537841.

It is an arithmetic number, because the mean of its divisors is an integer number (5371019703).

Almost surely, 2^21411003421 is an apocalyptic number.

It is an amenable number.

21411003421 is a deficient number, since it is larger than the sum of its proper divisors (73075391).

21411003421 is an equidigital number, since it uses as much as digits as its factorization.

21411003421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73075390.

The product of its (nonzero) digits is 192, while the sum is 19.

Adding to 21411003421 its reverse (12430011412), we get a palindrome (33841014833).

The spelling of 21411003421 in words is "twenty-one billion, four hundred eleven million, three thousand, four hundred twenty-one".