999997555311647 has 2 divisors, whose sum is σ = 999997555311648. Its totient is φ = 999997555311646.

The previous prime is 999997555311611. The next prime is 999997555311719. The reversal of 999997555311647 is 746113555799999.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 999997555311647 - 2¹⁰ = 999997555310623 is a prime.

It is a super-2 number, since 2×999997555311647² (a number of 31 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (999997555311947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499998777655823 + 499998777655824.

It is an arithmetic number, because the mean of its divisors is an integer number (499998777655824).

Almost surely, 2^{999997555311647} is an apocalyptic number.

999997555311647 is a deficient number, since it is larger than the sum of its proper divisors (1).

999997555311647 is an equidigital number, since it uses as much as digits as its factorization.

999997555311647 is an evil number, because the sum of its binary digits is even.

The product of its digits is 26040609000, while the sum is 89.

The spelling of 999997555311647 in words is "nine hundred ninety-nine trillion, nine hundred ninety-seven billion, five hundred fifty-five million, three hundred eleven thousand, six hundred forty-seven".