1285721571447 has 32 divisors (see below), whose sum is σ = 1995322959360. Its totient is φ = 816690124800.

The previous prime is 1285721571439. The next prime is 1285721571451. The reversal of 1285721571447 is 7441751275821.

1285721571447 is a `hidden beast` number, since 1 + 2 + 8 + 5 + 7 + 21 + 571 + 4 + 47 = 666.

It is not a de Polignac number, because 1285721571447 - 2³ = 1285721571439 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1285721571393 and 1285721571402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1285721571047) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3868429 + ... + 4187622.

It is an arithmetic number, because the mean of its divisors is an integer number (62353842480).

Almost surely, 2^{1285721571447} is an apocalyptic number.

1285721571447 is a deficient number, since it is larger than the sum of its proper divisors (709601387913).

1285721571447 is a wasteful number, since it uses less digits than its factorization.

1285721571447 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8056340 (or 8056334 counting only the distinct ones).

The product of its digits is 4390400, while the sum is 54.

The spelling of 1285721571447 in words is "one trillion, two hundred eighty-five billion, seven hundred twenty-one million, five hundred seventy-one thousand, four hundred forty-seven".