13405911381 has 12 divisors (see below), whose sum is σ = 19365098220. Its totient is φ = 8936810880.

The previous prime is 13405911371. The next prime is 13405911397. The reversal of 13405911381 is 18311950431.

It is a happy number.

13405911381 is a `hidden beast` number, since 1 + 34 + 0 + 591 + 1 + 38 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 8468600625 + 4937310756 = 92025^2 + 70266^2 .

It is not a de Polignac number, because 13405911381 - 2²³ = 13397522773 is a prime.

It is a super-2 number, since 2×13405911381² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13405911371) 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, 316315 + ... + 356183.

It is an arithmetic number, because the mean of its divisors is an integer number (1613758185).

Almost surely, 2^13405911381 is an apocalyptic number.

It is an amenable number.

13405911381 is a deficient number, since it is larger than the sum of its proper divisors (5959186839).

13405911381 is a wasteful number, since it uses less digits than its factorization.

13405911381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77236 (or 77233 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The spelling of 13405911381 in words is "thirteen billion, four hundred five million, nine hundred eleven thousand, three hundred eighty-one".