21213011144 has 24 divisors (see below), whose sum is σ = 43069319010. Its totient is φ = 9790619904.

The previous prime is 21213011123. The next prime is 21213011167. The reversal of 21213011144 is 44111031212.

It can be written as a sum of positive squares in 3 ways, for example, as 18046698244 + 3166312900 = 134338^2 + 56270^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 7843697 + ... + 7846400.

Almost surely, 2^21213011144 is an apocalyptic number.

It is an amenable number.

21213011144 is an abundant number, since it is smaller than the sum of its proper divisors (21856307866).

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

21213011144 is a wasteful number, since it uses less digits than its factorization.

21213011144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15690129 (or 15690112 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 20.

Adding to 21213011144 its reverse (44111031212), we get a palindrome (65324042356).

The spelling of 21213011144 in words is "twenty-one billion, two hundred thirteen million, eleven thousand, one hundred forty-four".