21504525355337 has 2 divisors, whose sum is σ = 21504525355338. Its totient is φ = 21504525355336.

The previous prime is 21504525355319. The next prime is 21504525355399. The reversal of 21504525355337 is 73355352540512.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15862090460176 + 5642434895161 = 3982724^2 + 2375381^2 .

It is a cyclic number.

It is not a de Polignac number, because 21504525355337 - 2³⁰ = 21503451613513 is a prime.

It is a super-2 number, since 2×21504525355337² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21504525355837) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10752262677668 + 10752262677669.

It is an arithmetic number, because the mean of its divisors is an integer number (10752262677669).

Almost surely, 2^{21504525355337} is an apocalyptic number.

It is an amenable number.

21504525355337 is a deficient number, since it is larger than the sum of its proper divisors (1).

21504525355337 is an equidigital number, since it uses as much as digits as its factorization.

21504525355337 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9450000, while the sum is 50.

Adding to 21504525355337 its reverse (73355352540512), we get a palindrome (94859877895849).

The spelling of 21504525355337 in words is "twenty-one trillion, five hundred four billion, five hundred twenty-five million, three hundred fifty-five thousand, three hundred thirty-seven".