21144333237 has 8 divisors (see below), whose sum is σ = 28455925536. Its totient is φ = 13964481552.

The previous prime is 21144333191. The next prime is 21144333307. The reversal of 21144333237 is 73233344112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21144333237 - 2⁷ = 21144333109 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21144333198 and 21144333207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21144333037) 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, 32934778 + ... + 32935419.

It is an arithmetic number, because the mean of its divisors is an integer number (3556990692).

Almost surely, 2^21144333237 is an apocalyptic number.

It is an amenable number.

21144333237 is a deficient number, since it is larger than the sum of its proper divisors (7311592299).

21144333237 is a wasteful number, since it uses less digits than its factorization.

21144333237 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65870307.

The product of its digits is 36288, while the sum is 33.

Adding to 21144333237 its reverse (73233344112), we get a palindrome (94377677349).

The spelling of 21144333237 in words is "twenty-one billion, one hundred forty-four million, three hundred thirty-three thousand, two hundred thirty-seven".