1271646540 has 120 divisors (see below), whose sum is σ = 4162767840. Its totient is φ = 324352512.

The previous prime is 1271646539. The next prime is 1271646557. The reversal of 1271646540 is 456461721.

1271646540 is a `hidden beast` number, since 1 + 2 + 7 + 1 + 646 + 5 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1271646495 and 1271646504.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 20196 + ... + 54324.

It is an arithmetic number, because the mean of its divisors is an integer number (34689732).

Almost surely, 2^1271646540 is an apocalyptic number.

1271646540 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 1271646540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2081383920).

1271646540 is an abundant number, since it is smaller than the sum of its proper divisors (2891121300).

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

1271646540 is a wasteful number, since it uses less digits than its factorization.

1271646540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34173 (or 34162 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 36.

The square root of 1271646540 is about 35660.1533928277. The cubic root of 1271646540 is about 1083.3999336307.

The spelling of 1271646540 in words is "one billion, two hundred seventy-one million, six hundred forty-six thousand, five hundred forty".