1381091786 has 8 divisors (see below), whose sum is σ = 2079699300. Its totient is φ = 687858688.

The previous prime is 1381091783. The next prime is 1381091797. The reversal of 1381091786 is 6871901831.

It can be written as a sum of positive squares in 2 ways, for example, as 1103236225 + 277855561 = 33215^2 + 16669^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (1381091783) 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, 1342961 + ... + 1343988.

Almost surely, 2^1381091786 is an apocalyptic number.

1381091786 is a deficient number, since it is larger than the sum of its proper divisors (698607514).

1381091786 is a wasteful number, since it uses less digits than its factorization.

1381091786 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2687208.

The product of its (nonzero) digits is 72576, while the sum is 44.

The square root of 1381091786 is about 37163.0432822717. The cubic root of 1381091786 is about 1113.6298091906.

The spelling of 1381091786 in words is "one billion, three hundred eighty-one million, ninety-one thousand, seven hundred eighty-six".