21213400144 has 40 divisors (see below), whose sum is σ = 41347095680. Its totient is φ = 10543367808.

The previous prime is 21213400129. The next prime is 21213400157. The reversal of 21213400144 is 44100431212.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1940197 + ... + 1951099.

It is an arithmetic number, because the mean of its divisors is an integer number (1033677392).

Almost surely, 2^21213400144 is an apocalyptic number.

It is an amenable number.

21213400144 is a deficient number, since it is larger than the sum of its proper divisors (20133695536).

21213400144 is a wasteful number, since it uses less digits than its factorization.

21213400144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11627 (or 11621 counting only the distinct ones).

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

Adding to 21213400144 its reverse (44100431212), we get a palindrome (65313831356).

The spelling of 21213400144 in words is "twenty-one billion, two hundred thirteen million, four hundred thousand, one hundred forty-four".