997551999955 has 32 divisors (see below), whose sum is σ = 1427635298304. Its totient is φ = 654257108736.

The previous prime is 997551999947. The next prime is 997551999959. The reversal of 997551999955 is 559999155799.

It is not a de Polignac number, because 997551999955 - 2³ = 997551999947 is a prime.

It is a super-2 number, since 2×997551999955² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (997551999959) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 23342167 + ... + 23384863.

It is an arithmetic number, because the mean of its divisors is an integer number (44613603072).

Almost surely, 2^997551999955 is an apocalyptic number.

997551999955 is a deficient number, since it is larger than the sum of its proper divisors (430083298349).

997551999955 is a wasteful number, since it uses less digits than its factorization.

997551999955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71755.

The product of its digits is 2325054375, while the sum is 82.

The spelling of 997551999955 in words is "nine hundred ninety-seven billion, five hundred fifty-one million, nine hundred ninety-nine thousand, nine hundred fifty-five".