12771440 has 80 divisors (see below), whose sum is σ = 33854976. Its totient is φ = 4435200.

The previous prime is 12771431. The next prime is 12771457. The reversal of 12771440 is 4417721.

It is a tau number, because it is divible by the number of its divisors (80).

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, 19925 + ... + 20555.

Almost surely, 2^12771440 is an apocalyptic number.

12771440 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 12771440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16927488).

12771440 is an abundant number, since it is smaller than the sum of its proper divisors (21083536).

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

12771440 is a wasteful number, since it uses less digits than its factorization.

12771440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 678 (or 672 counting only the distinct ones).

The product of its (nonzero) digits is 1568, while the sum is 26.

The square root of 12771440 is about 3573.7151537301. The cubic root of 12771440 is about 233.7473104440.

The spelling of 12771440 in words is "twelve million, seven hundred seventy-one thousand, four hundred forty".