11978520 has 64 divisors (see below), whose sum is σ = 36205920. Its totient is φ = 3170304.

The previous prime is 11978507. The next prime is 11978539. The reversal of 11978520 is 2587911.

11978520 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is a Cunningham number, because it is equal to 3461²-1.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20472 + ... + 21048.

Almost surely, 2^11978520 is an apocalyptic number.

11978520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 11978520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18102960).

11978520 is an abundant number, since it is smaller than the sum of its proper divisors (24227400).

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

11978520 is a wasteful number, since it uses less digits than its factorization.

11978520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 764 (or 760 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 33.

The square root of 11978520 is about 3460.9998555331. Note that the first 3 decimals coincide. The cubic root of 11978520 is about 228.8061643570.

It can be divided in two parts, 119785 and 20, that added together give a triangular number (119805 = T₄₈₉).

The spelling of 11978520 in words is "eleven million, nine hundred seventy-eight thousand, five hundred twenty".