21130021444 has 48 divisors (see below), whose sum is σ = 42494932480. Its totient is φ = 9005489280.

The previous prime is 21130021439. The next prime is 21130021447. The reversal of 21130021444 is 44412003112.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21130021447) 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, 7891834 + ... + 7894510.

Almost surely, 2^21130021444 is an apocalyptic number.

It is an amenable number.

21130021444 is an abundant number, since it is smaller than the sum of its proper divisors (21364911036).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21130021444 is a wasteful number, since it uses less digits than its factorization.

21130021444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4148 (or 4146 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 22.

Adding to 21130021444 its reverse (44412003112), we get a palindrome (65542024556).

The spelling of 21130021444 in words is "twenty-one billion, one hundred thirty million, twenty-one thousand, four hundred forty-four".