9281138421555 has 384 divisors, whose sum is σ = 23875643151360. Its totient is φ = 3350955847680.

The previous prime is 9281138421523. The next prime is 9281138421571. The reversal of 9281138421555 is 5551248311829.

It is a happy number.

9281138421555 is a `hidden beast` number, since 9 + 2 + 8 + 1 + 1 + 3 + 84 + 2 + 1 + 555 = 666.

It is not a de Polignac number, because 9281138421555 - 2⁵ = 9281138421523 is a prime.

It is a super-2 number, since 2×9281138421555² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 15792492 + ... + 16369638.

It is an arithmetic number, because the mean of its divisors is an integer number (62176154040).

Almost surely, 2^{9281138421555} is an apocalyptic number.

9281138421555 is an abundant number, since it is smaller than the sum of its proper divisors (14594504729805).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

9281138421555 is a wasteful number, since it uses less digits than its factorization.

9281138421555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 577216 (or 577203 counting only the distinct ones).

The product of its digits is 3456000, while the sum is 54.

The spelling of 9281138421555 in words is "nine trillion, two hundred eighty-one billion, one hundred thirty-eight million, four hundred twenty-one thousand, five hundred fifty-five".