21226232437 has 4 divisors (see below), whose sum is σ = 21337364736. Its totient is φ = 21115100140.

The previous prime is 21226232431. The next prime is 21226232471. The reversal of 21226232437 is 73423262212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21226232437 - 2³ = 21226232429 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21226232431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55565863 + ... + 55566244.

It is an arithmetic number, because the mean of its divisors is an integer number (5334341184).

Almost surely, 2^21226232437 is an apocalyptic number.

It is an amenable number.

21226232437 is a deficient number, since it is larger than the sum of its proper divisors (111132299).

21226232437 is a wasteful number, since it uses less digits than its factorization.

21226232437 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111132298.

The product of its digits is 48384, while the sum is 34.

Adding to 21226232437 its reverse (73423262212), we get a palindrome (94649494649).

The spelling of 21226232437 in words is "twenty-one billion, two hundred twenty-six million, two hundred thirty-two thousand, four hundred thirty-seven".