16409688557 has 2 divisors, whose sum is σ = 16409688558. Its totient is φ = 16409688556.

The previous prime is 16409688527. The next prime is 16409688563. The reversal of 16409688557 is 75588690461.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16186455076 + 223233481 = 127226^2 + 14941^2 .

It is an emirp because it is prime and its reverse (75588690461) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16409688557 - 2¹⁰ = 16409687533 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 16409688496 and 16409688505.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16409688517) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8204844278 + 8204844279.

It is an arithmetic number, because the mean of its divisors is an integer number (8204844279).

Almost surely, 2^16409688557 is an apocalyptic number.

It is an amenable number.

16409688557 is a deficient number, since it is larger than the sum of its proper divisors (1).

16409688557 is an equidigital number, since it uses as much as digits as its factorization.

16409688557 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 14515200, while the sum is 59.

The spelling of 16409688557 in words is "sixteen billion, four hundred nine million, six hundred eighty-eight thousand, five hundred fifty-seven".