381028315581 has 12 divisors (see below), whose sum is σ = 556558214940. Its totient is φ = 251164731840.

The previous prime is 381028315579. The next prime is 381028315589. The reversal of 381028315581 is 185513820183.

381028315581 is a `hidden beast` number, since 3 + 8 + 10 + 2 + 83 + 1 + 558 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 78885709956 + 302142605625 = 280866^2 + 549675^2 .

It is not a de Polignac number, because 381028315581 - 2¹ = 381028315579 is a prime.

It is a super-2 number, since 2×381028315581² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (381028315589) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 237844590 + ... + 237846191.

It is an arithmetic number, because the mean of its divisors is an integer number (46379851245).

Almost surely, 2^381028315581 is an apocalyptic number.

It is an amenable number.

381028315581 is a deficient number, since it is larger than the sum of its proper divisors (175529899359).

381028315581 is a wasteful number, since it uses less digits than its factorization.

381028315581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 475690876 (or 475690873 counting only the distinct ones).

The product of its (nonzero) digits is 230400, while the sum is 45.

The spelling of 381028315581 in words is "three hundred eighty-one billion, twenty-eight million, three hundred fifteen thousand, five hundred eighty-one".