1138237821 has 48 divisors (see below), whose sum is σ = 1944708480. Its totient is φ = 628024320.

The previous prime is 1138237801. The next prime is 1138237843. The reversal of 1138237821 is 1287328311.

It is not a de Polignac number, because 1138237821 - 2¹⁰ = 1138236797 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1138237801) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 238741 + ... + 243461.

It is an arithmetic number, because the mean of its divisors is an integer number (40514760).

Almost surely, 2^1138237821 is an apocalyptic number.

It is an amenable number.

1138237821 is a deficient number, since it is larger than the sum of its proper divisors (806470659).

1138237821 is a wasteful number, since it uses less digits than its factorization.

1138237821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4866 (or 4863 counting only the distinct ones).

The product of its digits is 16128, while the sum is 36.

The square root of 1138237821 is about 33737.7803211770. The cubic root of 1138237821 is about 1044.1053891275.

The spelling of 1138237821 in words is "one billion, one hundred thirty-eight million, two hundred thirty-seven thousand, eight hundred twenty-one".