11800921 has 4 divisors (see below), whose sum is σ = 12873744. Its totient is φ = 10728100.

The previous prime is 11800913. The next prime is 11800931. The reversal of 11800921 is 12900811.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 11800921 - 2³ = 11800913 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11800892 and 11800901.

It is not an unprimeable number, because it can be changed into a prime (11800931) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 536395 + ... + 536416.

It is an arithmetic number, because the mean of its divisors is an integer number (3218436).

Almost surely, 2^11800921 is an apocalyptic number.

11800921 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

11800921 is a deficient number, since it is larger than the sum of its proper divisors (1072823).

11800921 is a wasteful number, since it uses less digits than its factorization.

11800921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1072822.

The product of its (nonzero) digits is 144, while the sum is 22.

The square root of 11800921 is about 3435.2468615807. The cubic root of 11800921 is about 227.6697344600.

It can be divided in two parts, 11800 and 921, that added together give a palindrome (12721).

The spelling of 11800921 in words is "eleven million, eight hundred thousand, nine hundred twenty-one".