1271815976772 has 576 divisors, whose sum is σ = 4090775270400. Its totient is φ = 340491755520.

The previous prime is 1271815976771. The next prime is 1271815976801. The reversal of 1271815976772 is 2776795181721.

1271815976772 is a `hidden beast` number, since 1 + 27 + 18 + 1 + 597 + 6 + 7 + 7 + 2 = 666.

It is a Smith number, since the sum of its digits (63) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (1271815976771) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 390245679 + ... + 390248937.

It is an arithmetic number, because the mean of its divisors is an integer number (7102040400).

Almost surely, 2^{1271815976772} is an apocalyptic number.

1271815976772 is a gapful number since it is divisible by the number (12) 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 1271815976772, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2045387635200).

1271815976772 is an abundant number, since it is smaller than the sum of its proper divisors (2818959293628).

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

1271815976772 is a wasteful number, since it uses less digits than its factorization.

1271815976772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3438 (or 3424 counting only the distinct ones).

The product of its digits is 20744640, while the sum is 63.

The spelling of 1271815976772 in words is "one trillion, two hundred seventy-one billion, eight hundred fifteen million, nine hundred seventy-six thousand, seven hundred seventy-two".