1191010020 has 48 divisors (see below), whose sum is σ = 3424964928. Its totient is φ = 309018240.

The previous prime is 1191010013. The next prime is 1191010039. The reversal of 1191010020 is 200101911.

It is a Harshad number since it is a multiple of its sum of digits (15).

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 in 15 ways as a sum of consecutive naturals, for example, 266026 + ... + 270465.

It is an arithmetic number, because the mean of its divisors is an integer number (71353436).

Almost surely, 2^1191010020 is an apocalyptic number.

1191010020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1191010020 is an abundant number, since it is smaller than the sum of its proper divisors (2233954908).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1191010020 is a wasteful number, since it uses less digits than its factorization.

1191010020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 536540 (or 536538 counting only the distinct ones).

The product of its (nonzero) digits is 18, while the sum is 15.

The square root of 1191010020 is about 34511.0130248302. The cubic root of 1191010020 is about 1059.9982259375.

Adding to 1191010020 its reverse (200101911), we get a palindrome (1391111931).

The spelling of 1191010020 in words is "one billion, one hundred ninety-one million, ten thousand, twenty".