11971620 has 36 divisors (see below), whose sum is σ = 36314460. Its totient is φ = 3192384.

The previous prime is 11971607. The next prime is 11971637. The reversal of 11971620 is 2617911.

It can be written as a sum of positive squares in 2 ways, for example, as 7485696 + 4485924 = 2736^2 + 2118^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 33075 + ... + 33434.

It is an arithmetic number, because the mean of its divisors is an integer number (1008735).

Almost surely, 2^11971620 is an apocalyptic number.

11971620 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

11971620 is an abundant number, since it is smaller than the sum of its proper divisors (24342840).

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

11971620 is a wasteful number, since it uses less digits than its factorization.

11971620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66524 (or 66519 counting only the distinct ones).

The product of its (nonzero) digits is 756, while the sum is 27.

The square root of 11971620 is about 3460.0028901722. The cubic root of 11971620 is about 228.7622227635.

The spelling of 11971620 in words is "eleven million, nine hundred seventy-one thousand, six hundred twenty".