11981970 has 288 divisors, whose sum is σ = 44815680. Its totient is φ = 2177280.

The previous prime is 11981941. The next prime is 11981971. The reversal of 11981970 is 7918911.

11981970 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a harmonic number, since the harmonic mean of its divisors is an integer.

It is a Curzon number.

It is a nialpdrome in base 8.

It is a zygodrome in base 8.

It is not an unprimeable number, because it can be changed into a prime (11981971) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 630621 + ... + 630639.

It is an arithmetic number, because the mean of its divisors is an integer number (155610).

Almost surely, 2^11981970 is an apocalyptic number.

11981970 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 11981970, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22407840).

11981970 is an abundant number, since it is smaller than the sum of its proper divisors (32833710).

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

11981970 is a wasteful number, since it uses less digits than its factorization.

11981970 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70 (or 60 counting only the distinct ones).

The product of its (nonzero) digits is 4536, while the sum is 36.

The square root of 11981970 is about 3461.4982305354. The cubic root of 11981970 is about 228.8281288261.

The spelling of 11981970 in words is "eleven million, nine hundred eighty-one thousand, nine hundred seventy".