1988959555491 has 8 divisors (see below), whose sum is σ = 2737492721664. Its totient is φ = 1283199713160.

The previous prime is 1988959555489. The next prime is 1988959555507. The reversal of 1988959555491 is 1945559598891.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1988959555491 - 2¹ = 1988959555489 is a prime.

It is a super-2 number, since 2×1988959555491² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1988959555441) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10693330851 + ... + 10693331036.

It is an arithmetic number, because the mean of its divisors is an integer number (342186590208).

Almost surely, 2^{1988959555491} is an apocalyptic number.

1988959555491 is a deficient number, since it is larger than the sum of its proper divisors (748533166173).

1988959555491 is a wasteful number, since it uses less digits than its factorization.

1988959555491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21386661921.

The product of its digits is 1049760000, while the sum is 78.

The spelling of 1988959555491 in words is "one trillion, nine hundred eighty-eight billion, nine hundred fifty-nine million, five hundred fifty-five thousand, four hundred ninety-one".