21212508127437 has 24 divisors (see below), whose sum is σ = 33476492443680. Its totient is φ = 12836557046880.

The previous prime is 21212508127411. The next prime is 21212508127483. The reversal of 21212508127437 is 73472180521212.

21212508127437 is a `hidden beast` number, since 2 + 1 + 2 + 12 + 508 + 127 + 4 + 3 + 7 = 666.

It is not a de Polignac number, because 21212508127437 - 2¹⁸ = 21212507865293 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21212508127392 and 21212508127401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21212508122437) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 162505138 + ... + 162635619.

It is an arithmetic number, because the mean of its divisors is an integer number (1394853851820).

Almost surely, 2^{21212508127437} is an apocalyptic number.

It is an amenable number.

21212508127437 is a deficient number, since it is larger than the sum of its proper divisors (12263984316243).

21212508127437 is a wasteful number, since it uses less digits than its factorization.

21212508127437 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 325141433 (or 325141430 counting only the distinct ones).

The product of its (nonzero) digits is 376320, while the sum is 45.

Adding to 21212508127437 its reverse (73472180521212), we get a palindrome (94684688648649).

The spelling of 21212508127437 in words is "twenty-one trillion, two hundred twelve billion, five hundred eight million, one hundred twenty-seven thousand, four hundred thirty-seven".