10555516421 has 2 divisors, whose sum is σ = 10555516422. Its totient is φ = 10555516420.

The previous prime is 10555516397. The next prime is 10555516423. The reversal of 10555516421 is 12461555501.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9103068100 + 1452448321 = 95410^2 + 38111^2 .

It is a cyclic number.

It is not a de Polignac number, because 10555516421 - 2⁶ = 10555516357 is a prime.

It is a super-2 number, since 2×10555516421² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

Together with 10555516423, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (10555516423) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5277758210 + 5277758211.

It is an arithmetic number, because the mean of its divisors is an integer number (5277758211).

Almost surely, 2^10555516421 is an apocalyptic number.

It is an amenable number.

10555516421 is a deficient number, since it is larger than the sum of its proper divisors (1).

10555516421 is an equidigital number, since it uses as much as digits as its factorization.

10555516421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 30000, while the sum is 35.

The spelling of 10555516421 in words is "ten billion, five hundred fifty-five million, five hundred sixteen thousand, four hundred twenty-one".