21324306737 has 2 divisors, whose sum is σ = 21324306738. Its totient is φ = 21324306736.

The previous prime is 21324306713. The next prime is 21324306761. The reversal of 21324306737 is 73760342312.

It is a balanced prime because it is at equal distance from previous prime (21324306713) and next prime (21324306761).

It can be written as a sum of positive squares in only one way, i.e., 15158288161 + 6166018576 = 123119^2 + 78524^2 .

It is a cyclic number.

It is not a de Polignac number, because 21324306737 - 2¹⁸ = 21324044593 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21324306737.

It is not a weakly prime, because it can be changed into another prime (21324306137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10662153368 + 10662153369.

It is an arithmetic number, because the mean of its divisors is an integer number (10662153369).

Almost surely, 2^21324306737 is an apocalyptic number.

It is an amenable number.

21324306737 is a deficient number, since it is larger than the sum of its proper divisors (1).

21324306737 is an equidigital number, since it uses as much as digits as its factorization.

21324306737 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 127008, while the sum is 38.

The spelling of 21324306737 in words is "twenty-one billion, three hundred twenty-four million, three hundred six thousand, seven hundred thirty-seven".