11821947 has 16 divisors (see below), whose sum is σ = 16291968. Its totient is φ = 7620480.

The previous prime is 11821913. The next prime is 11821961. The reversal of 11821947 is 74912811.

It is not a de Polignac number, because 11821947 - 2⁶ = 11821883 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11821967) 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, 14172 + ... + 14982.

It is an arithmetic number, because the mean of its divisors is an integer number (1018248).

Almost surely, 2^11821947 is an apocalyptic number.

11821947 is a deficient number, since it is larger than the sum of its proper divisors (4470021).

11821947 is a wasteful number, since it uses less digits than its factorization.

11821947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 970.

The product of its digits is 4032, while the sum is 33.

The square root of 11821947 is about 3438.3058328194. The cubic root of 11821947 is about 227.8048692125.

The spelling of 11821947 in words is "eleven million, eight hundred twenty-one thousand, nine hundred forty-seven".