21003313144 has 64 divisors (see below), whose sum is σ = 46040970240. Its totient is φ = 8885036160.

The previous prime is 21003313091. The next prime is 21003313147. The reversal of 21003313144 is 44131330012.

It is a super-2 number, since 2×21003313144² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21003313147) 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, 65344 + ... + 215119.

It is an arithmetic number, because the mean of its divisors is an integer number (719390160).

Almost surely, 2^21003313144 is an apocalyptic number.

It is an amenable number.

21003313144 is an abundant number, since it is smaller than the sum of its proper divisors (25037657096).

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

21003313144 is a wasteful number, since it uses less digits than its factorization.

21003313144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 280540 (or 280536 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 22.

Adding to 21003313144 its reverse (44131330012), we get a palindrome (65134643156).

The spelling of 21003313144 in words is "twenty-one billion, three million, three hundred thirteen thousand, one hundred forty-four".