1281561526272 has 136 divisors (see below), whose sum is σ = 3535330897440. Its totient is φ = 412454748160.

The previous prime is 1281561526237. The next prime is 1281561526277. The reversal of 1281561526272 is 2726251651821.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1281561526277) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5589247 + ... + 5814017.

Almost surely, 2^{1281561526272} is an apocalyptic number.

1281561526272 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 1281561526272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1767665448720).

1281561526272 is an abundant number, since it is smaller than the sum of its proper divisors (2253769371168).

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

1281561526272 is an frugal number, since it uses more digits than its factorization.

1281561526272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 224835 (or 224805 counting only the distinct ones).

The product of its digits is 806400, while the sum is 48.

The spelling of 1281561526272 in words is "one trillion, two hundred eighty-one billion, five hundred sixty-one million, five hundred twenty-six thousand, two hundred seventy-two".