1381228166 has 4 divisors (see below), whose sum is σ = 2071842252. Its totient is φ = 690614082.

The previous prime is 1381228141. The next prime is 1381228171. The reversal of 1381228166 is 6618221831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 6618221831 = 13 ⋅509093987.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 345307040 + ... + 345307043.

It is an arithmetic number, because the mean of its divisors is an integer number (517960563).

Almost surely, 2^1381228166 is an apocalyptic number.

1381228166 is a deficient number, since it is larger than the sum of its proper divisors (690614086).

1381228166 is an equidigital number, since it uses as much as digits as its factorization.

1381228166 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 690614085.

The product of its digits is 27648, while the sum is 38.

The square root of 1381228166 is about 37164.8781243797. The cubic root of 1381228166 is about 1113.6664642090. Note that the first 3 decimals are identical.

Adding to 1381228166 its reverse (6618221831), we get a palindrome (7999449997).

The spelling of 1381228166 in words is "one billion, three hundred eighty-one million, two hundred twenty-eight thousand, one hundred sixty-six".