21477430752961 has 2 divisors, whose sum is σ = 21477430752962. Its totient is φ = 21477430752960.

The previous prime is 21477430752913. The next prime is 21477430752971. The reversal of 21477430752961 is 16925703477412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15668487222336 + 5808943530625 = 3958344^2 + 2410175^2 .

It is a cyclic number.

It is not a de Polignac number, because 21477430752961 - 2¹¹ = 21477430750913 is a prime.

It is a super-2 number, since 2×21477430752961² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21477430752896 and 21477430752905.

It is not a weakly prime, because it can be changed into another prime (21477430752971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10738715376480 + 10738715376481.

It is an arithmetic number, because the mean of its divisors is an integer number (10738715376481).

Almost surely, 2^{21477430752961} is an apocalyptic number.

It is an amenable number.

21477430752961 is a deficient number, since it is larger than the sum of its proper divisors (1).

21477430752961 is an equidigital number, since it uses as much as digits as its factorization.

21477430752961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17781120, while the sum is 58.

The spelling of 21477430752961 in words is "twenty-one trillion, four hundred seventy-seven billion, four hundred thirty million, seven hundred fifty-two thousand, nine hundred sixty-one".