21464780724577 has 2 divisors, whose sum is σ = 21464780724578. Its totient is φ = 21464780724576.

The previous prime is 21464780724557. The next prime is 21464780724581. The reversal of 21464780724577 is 77542708746412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21382402540321 + 82378184256 = 4624111^2 + 287016^2 .

It is a cyclic number.

It is not a de Polignac number, because 21464780724577 - 2²³ = 21464772335969 is a prime.

It is a super-2 number, since 2×21464780724577² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21464780724557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10732390362288 + 10732390362289.

It is an arithmetic number, because the mean of its divisors is an integer number (10732390362289).

Almost surely, 2^{21464780724577} is an apocalyptic number.

It is an amenable number.

21464780724577 is a deficient number, since it is larger than the sum of its proper divisors (1).

21464780724577 is an equidigital number, since it uses as much as digits as its factorization.

21464780724577 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 147517440, while the sum is 64.

The spelling of 21464780724577 in words is "twenty-one trillion, four hundred sixty-four billion, seven hundred eighty million, seven hundred twenty-four thousand, five hundred seventy-seven".