11921905 has 4 divisors (see below), whose sum is σ = 14306292. Its totient is φ = 9537520.

The previous prime is 11921867. The next prime is 11921933. The reversal of 11921905 is 50912911.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5987809 + 5934096 = 2447^2 + 2436^2 .

It is not a de Polignac number, because 11921905 - 2¹¹ = 11919857 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1192186 + ... + 1192195.

It is an arithmetic number, because the mean of its divisors is an integer number (3576573).

Almost surely, 2^11921905 is an apocalyptic number.

It is an amenable number.

11921905 is a deficient number, since it is larger than the sum of its proper divisors (2384387).

11921905 is an equidigital number, since it uses as much as digits as its factorization.

11921905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2384386.

The product of its (nonzero) digits is 810, while the sum is 28.

The square root of 11921905 is about 3452.8111735222. The cubic root of 11921905 is about 228.4451202262.

The spelling of 11921905 in words is "eleven million, nine hundred twenty-one thousand, nine hundred five".