1168156821 has 16 divisors (see below), whose sum is σ = 1750283136. Its totient is φ = 687610176.

The previous prime is 1168156813. The next prime is 1168156837. The reversal of 1168156821 is 1286518611.

It is not a de Polignac number, because 1168156821 - 2³ = 1168156813 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1168156821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1168156811) 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, 650250 + ... + 652043.

It is an arithmetic number, because the mean of its divisors is an integer number (109392696).

Almost surely, 2^1168156821 is an apocalyptic number.

It is an amenable number.

1168156821 is a deficient number, since it is larger than the sum of its proper divisors (582126315).

1168156821 is a wasteful number, since it uses less digits than its factorization.

1168156821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1302332.

The product of its digits is 23040, while the sum is 39.

The square root of 1168156821 is about 34178.3092179821. The cubic root of 1168156821 is about 1053.1746160894.

The spelling of 1168156821 in words is "one billion, one hundred sixty-eight million, one hundred fifty-six thousand, eight hundred twenty-one".