21444420415 has 96 divisors (see below), whose sum is σ = 31460607360. Its totient is φ = 13946634240.

The previous prime is 21444420409. The next prime is 21444420463. The reversal of 21444420415 is 51402444412.

It is not a de Polignac number, because 21444420415 - 2⁷ = 21444420287 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 63633127 + ... + 63633463.

It is an arithmetic number, because the mean of its divisors is an integer number (327714660).

Almost surely, 2^21444420415 is an apocalyptic number.

21444420415 is a deficient number, since it is larger than the sum of its proper divisors (10016186945).

21444420415 is a wasteful number, since it uses less digits than its factorization.

21444420415 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 673 (or 662 counting only the distinct ones).

The product of its (nonzero) digits is 20480, while the sum is 31.

Adding to 21444420415 its reverse (51402444412), we get a palindrome (72846864827).

The spelling of 21444420415 in words is "twenty-one billion, four hundred forty-four million, four hundred twenty thousand, four hundred fifteen".