1381860639 has 6 divisors (see below), whose sum is σ = 1996020936. Its totient is φ = 921240420.

The previous prime is 1381860607. The next prime is 1381860673. The reversal of 1381860639 is 9360681831.

It is a happy number.

1381860639 is a `hidden beast` number, since 1 + 3 + 8 + 1 + 8 + 6 + 0 + 639 = 666.

It is not a de Polignac number, because 1381860639 - 2⁵ = 1381860607 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1381860594 and 1381860603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1381860439) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 76770027 + ... + 76770044.

It is an arithmetic number, because the mean of its divisors is an integer number (332670156).

Almost surely, 2^1381860639 is an apocalyptic number.

1381860639 is a deficient number, since it is larger than the sum of its proper divisors (614160297).

1381860639 is a wasteful number, since it uses less digits than its factorization.

1381860639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 153540077 (or 153540074 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The square root of 1381860639 is about 37173.3861653737. The cubic root of 1381860639 is about 1113.8364232120.

The spelling of 1381860639 in words is "one billion, three hundred eighty-one million, eight hundred sixty thousand, six hundred thirty-nine".