21107022637 has 2 divisors, whose sum is σ = 21107022638. Its totient is φ = 21107022636.

The previous prime is 21107022631. The next prime is 21107022647. The reversal of 21107022637 is 73622070112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20331622921 + 775399716 = 142589^2 + 27846^2 .

It is a cyclic number.

It is not a de Polignac number, because 21107022637 - 2¹¹ = 21107020589 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21107022599 and 21107022608.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21107022631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10553511318 + 10553511319.

It is an arithmetic number, because the mean of its divisors is an integer number (10553511319).

Almost surely, 2^21107022637 is an apocalyptic number.

It is an amenable number.

21107022637 is a deficient number, since it is larger than the sum of its proper divisors (1).

21107022637 is an equidigital number, since it uses as much as digits as its factorization.

21107022637 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7056, while the sum is 31.

Adding to 21107022637 its reverse (73622070112), we get a palindrome (94729092749).

The spelling of 21107022637 in words is "twenty-one billion, one hundred seven million, twenty-two thousand, six hundred thirty-seven".