1238381906 has 4 divisors (see below), whose sum is σ = 1857572862. Its totient is φ = 619190952.

The previous prime is 1238381899. The next prime is 1238381951. The reversal of 1238381906 is 6091838321.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 6091838321 = 1583 ⋅3848287.

It can be written as a sum of positive squares in only one way, i.e., 1065696025 + 172685881 = 32645^2 + 13141^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 309595475 + ... + 309595478.

Almost surely, 2^1238381906 is an apocalyptic number.

1238381906 is a deficient number, since it is larger than the sum of its proper divisors (619190956).

1238381906 is an equidigital number, since it uses as much as digits as its factorization.

1238381906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 619190955.

The product of its (nonzero) digits is 62208, while the sum is 41.

The square root of 1238381906 is about 35190.6508322878. The cubic root of 1238381906 is about 1073.8695615636.

The spelling of 1238381906 in words is "one billion, two hundred thirty-eight million, three hundred eighty-one thousand, nine hundred six".