21211012144 has 20 divisors (see below), whose sum is σ = 46967241424. Its totient is φ = 9090433728.

The previous prime is 21211012117. The next prime is 21211012187. The reversal of 21211012144 is 44121011212.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 94691907 + ... + 94692130.

Almost surely, 2^21211012144 is an apocalyptic number.

It is an amenable number.

21211012144 is an abundant number, since it is smaller than the sum of its proper divisors (25756229280).

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

21211012144 is a wasteful number, since it uses less digits than its factorization.

21211012144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 189384052 (or 189384046 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 21211012144 its reverse (44121011212), we get a palindrome (65332023356).

The spelling of 21211012144 in words is "twenty-one billion, two hundred eleven million, twelve thousand, one hundred forty-four".