21015007037 has 2 divisors, whose sum is σ = 21015007038. Its totient is φ = 21015007036.

The previous prime is 21015007033. The next prime is 21015007073. The reversal of 21015007037 is 73070051012.

Together with next prime (21015007073) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15065353081 + 5949653956 = 122741^2 + 77134^2 .

It is a cyclic number.

It is not a de Polignac number, because 21015007037 - 2² = 21015007033 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21015006997 and 21015007015.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21015007033) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10507503518 + 10507503519.

It is an arithmetic number, because the mean of its divisors is an integer number (10507503519).

Almost surely, 2^21015007037 is an apocalyptic number.

It is an amenable number.

21015007037 is a deficient number, since it is larger than the sum of its proper divisors (1).

21015007037 is an equidigital number, since it uses as much as digits as its factorization.

21015007037 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1470, while the sum is 26.

Adding to 21015007037 its reverse (73070051012), we get a palindrome (94085058049).

The spelling of 21015007037 in words is "twenty-one billion, fifteen million, seven thousand, thirty-seven".