384121085981 has 4 divisors (see below), whose sum is σ = 397366640700. Its totient is φ = 370875531264.

The previous prime is 384121085977. The next prime is 384121086007. The reversal of 384121085981 is 189580121483.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 189580121483 = 31849 ⋅5952467.

It can be written as a sum of positive squares in 2 ways, for example, as 164727209956 + 219393876025 = 405866^2 + 468395^2 .

It is a cyclic number.

It is not a de Polignac number, because 384121085981 - 2² = 384121085977 is a prime.

It is a super-2 number, since 2×384121085981² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (384121085911) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6622777316 + ... + 6622777373.

It is an arithmetic number, because the mean of its divisors is an integer number (99341660175).

Almost surely, 2^384121085981 is an apocalyptic number.

It is an amenable number.

384121085981 is a deficient number, since it is larger than the sum of its proper divisors (13245554719).

384121085981 is a wasteful number, since it uses less digits than its factorization.

384121085981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13245554718.

The product of its (nonzero) digits is 552960, while the sum is 50.

The spelling of 384121085981 in words is "three hundred eighty-four billion, one hundred twenty-one million, eighty-five thousand, nine hundred eighty-one".