1138121805 has 8 divisors (see below), whose sum is σ = 1820994912. Its totient is φ = 606998288.

The previous prime is 1138121783. The next prime is 1138121821. The reversal of 1138121805 is 5081218311.

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

It is a cyclic number.

It is not a de Polignac number, because 1138121805 - 2⁹ = 1138121293 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 37937379 + ... + 37937408.

It is an arithmetic number, because the mean of its divisors is an integer number (227624364).

Almost surely, 2^1138121805 is an apocalyptic number.

1138121805 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1138121805 is a deficient number, since it is larger than the sum of its proper divisors (682873107).

1138121805 is an equidigital number, since it uses as much as digits as its factorization.

1138121805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75874795.

The product of its (nonzero) digits is 1920, while the sum is 30.

The square root of 1138121805 is about 33736.0608992811. The cubic root of 1138121805 is about 1044.0699141021.

The spelling of 1138121805 in words is "one billion, one hundred thirty-eight million, one hundred twenty-one thousand, eight hundred five".