16426620557 has 2 divisors, whose sum is σ = 16426620558. Its totient is φ = 16426620556.

The previous prime is 16426620517. The next prime is 16426620571. The reversal of 16426620557 is 75502662461.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14165998441 + 2260622116 = 119021^2 + 47546^2 .

It is a cyclic number.

It is not a de Polignac number, because 16426620557 - 2¹² = 16426616461 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16426620517) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8213310278 + 8213310279.

It is an arithmetic number, because the mean of its divisors is an integer number (8213310279).

Almost surely, 2^16426620557 is an apocalyptic number.

It is an amenable number.

16426620557 is a deficient number, since it is larger than the sum of its proper divisors (1).

16426620557 is an equidigital number, since it uses as much as digits as its factorization.

16426620557 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 604800, while the sum is 44.

The spelling of 16426620557 in words is "sixteen billion, four hundred twenty-six million, six hundred twenty thousand, five hundred fifty-seven".