21420207037 has 2 divisors, whose sum is σ = 21420207038. Its totient is φ = 21420207036.

The previous prime is 21420206999. The next prime is 21420207101. The reversal of 21420207037 is 73070202412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11328196356 + 10092010681 = 106434^2 + 100459^2 .

It is a cyclic number.

It is not a de Polignac number, because 21420207037 - 2¹¹ = 21420204989 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21420206996 and 21420207014.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21420207637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10710103518 + 10710103519.

It is an arithmetic number, because the mean of its divisors is an integer number (10710103519).

Almost surely, 2^21420207037 is an apocalyptic number.

It is an amenable number.

21420207037 is a deficient number, since it is larger than the sum of its proper divisors (1).

21420207037 is an equidigital number, since it uses as much as digits as its factorization.

21420207037 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4704, while the sum is 28.

Adding to 21420207037 its reverse (73070202412), we get a palindrome (94490409449).

The spelling of 21420207037 in words is "twenty-one billion, four hundred twenty million, two hundred seven thousand, thirty-seven".