21421446331 has 4 divisors (see below), whose sum is σ = 21621646872. Its totient is φ = 21221245792.

The previous prime is 21421446329. The next prime is 21421446367. The reversal of 21421446331 is 13364412412.

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 21421446331 - 2¹ = 21421446329 is a prime.

It is a super-2 number, since 2×21421446331² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21421446293 and 21421446302.

It is not an unprimeable number, because it can be changed into a prime (21421446131) 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, 100100110 + ... + 100100323.

It is an arithmetic number, because the mean of its divisors is an integer number (5405411718).

Almost surely, 2^21421446331 is an apocalyptic number.

21421446331 is a deficient number, since it is larger than the sum of its proper divisors (200200541).

21421446331 is a wasteful number, since it uses less digits than its factorization.

21421446331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 200200540.

The product of its digits is 13824, while the sum is 31.

Adding to 21421446331 its reverse (13364412412), we get a palindrome (34785858743).

The spelling of 21421446331 in words is "twenty-one billion, four hundred twenty-one million, four hundred forty-six thousand, three hundred thirty-one".