21230221037 has 2 divisors, whose sum is σ = 21230221038. Its totient is φ = 21230221036.

The previous prime is 21230221013. The next prime is 21230221039. The reversal of 21230221037 is 73012203212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18445442596 + 2784778441 = 135814^2 + 52771^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21230221037 is a prime.

Together with 21230221039, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21230221039) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10615110518 + 10615110519.

It is an arithmetic number, because the mean of its divisors is an integer number (10615110519).

Almost surely, 2^21230221037 is an apocalyptic number.

It is an amenable number.

21230221037 is a deficient number, since it is larger than the sum of its proper divisors (1).

21230221037 is an equidigital number, since it uses as much as digits as its factorization.

21230221037 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1008, while the sum is 23.

Adding to 21230221037 its reverse (73012203212), we get a palindrome (94242424249).

The spelling of 21230221037 in words is "twenty-one billion, two hundred thirty million, two hundred twenty-one thousand, thirty-seven".