1165643020 has 48 divisors (see below), whose sum is σ = 2495652768. Its totient is φ = 457241600.

The previous prime is 1165643009. The next prime is 1165643021. The reversal of 1165643020 is 203465611.

It is a self number, because there is not a number n which added to its sum of digits gives 1165643020.

It is not an unprimeable number, because it can be changed into a prime (1165643021) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 213444 + ... + 218836.

It is an arithmetic number, because the mean of its divisors is an integer number (51992766).

Almost surely, 2^1165643020 is an apocalyptic number.

1165643020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1165643020 is an abundant number, since it is smaller than the sum of its proper divisors (1330009748).

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

1165643020 is a wasteful number, since it uses less digits than its factorization.

1165643020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5610 (or 5608 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 1165643020 is about 34141.5146119794. The cubic root of 1165643020 is about 1052.4186180664.

The spelling of 1165643020 in words is "one billion, one hundred sixty-five million, six hundred forty-three thousand, twenty".