21533250144 has 48 divisors (see below), whose sum is σ = 64599752448. Its totient is φ = 6152356992.

The previous prime is 21533250043. The next prime is 21533250149. The reversal of 21533250144 is 44105233512.

It is a tau number, because it is divible by the number of its divisors (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21533250149) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16021092 + ... + 16022435.

It is an arithmetic number, because the mean of its divisors is an integer number (1345828176).

Almost surely, 2^21533250144 is an apocalyptic number.

21533250144 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21533250144 is an abundant number, since it is smaller than the sum of its proper divisors (43066502304).

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

21533250144 is a wasteful number, since it uses less digits than its factorization.

21533250144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32043547 (or 32043539 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 30.

Adding to 21533250144 its reverse (44105233512), we get a palindrome (65638483656).

The spelling of 21533250144 in words is "twenty-one billion, five hundred thirty-three million, two hundred fifty thousand, one hundred forty-four".