1271885440 has 128 divisors (see below), whose sum is σ = 3495352320. Its totient is φ = 433520640.

The previous prime is 1271885431. The next prime is 1271885473. The reversal of 1271885440 is 445881721.

It is a tau number, because it is divible by the number of its divisors (128).

It is a hoax number, since the sum of its digits (40) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 1271885393 and 1271885402.

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, 863905 + ... + 865375.

It is an arithmetic number, because the mean of its divisors is an integer number (27307440).

Almost surely, 2^1271885440 is an apocalyptic number.

1271885440 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 1271885440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1747676160).

1271885440 is an abundant number, since it is smaller than the sum of its proper divisors (2223466880).

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

1271885440 is a wasteful number, since it uses less digits than its factorization.

1271885440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1690 (or 1678 counting only the distinct ones).

The product of its (nonzero) digits is 71680, while the sum is 40.

The square root of 1271885440 is about 35663.5029126417. The cubic root of 1271885440 is about 1083.4677742949.

The spelling of 1271885440 in words is "one billion, two hundred seventy-one million, eight hundred eighty-five thousand, four hundred forty".