1191021038 has 4 divisors (see below), whose sum is σ = 1786531560. Its totient is φ = 595510518.

The previous prime is 1191020893. The next prime is 1191021043. The reversal of 1191021038 is 8301201911.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8301201911 = 433 ⋅19171367.

It is a super-2 number, since 2×1191021038² = 2837062225917194888, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1191020998 and 1191021016.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 297755258 + ... + 297755261.

It is an arithmetic number, because the mean of its divisors is an integer number (446632890).

Almost surely, 2^1191021038 is an apocalyptic number.

1191021038 is a deficient number, since it is larger than the sum of its proper divisors (595510522).

1191021038 is an equidigital number, since it uses as much as digits as its factorization.

1191021038 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 595510521.

The product of its (nonzero) digits is 432, while the sum is 26.

The square root of 1191021038 is about 34511.1726546636. The cubic root of 1191021038 is about 1060.0014945986.

Adding to 1191021038 its reverse (8301201911), we get a palindrome (9492222949).

The spelling of 1191021038 in words is "one billion, one hundred ninety-one million, twenty-one thousand, thirty-eight".