1296138261600 has 1152 divisors, whose sum is σ = 5797308948480. Its totient is φ = 272152535040.

The previous prime is 1296138261563. The next prime is 1296138261623. The reversal of 1296138261600 is 61628316921.

1296138261600 is a `hidden beast` number, since 1 + 2 + 9 + 6 + 1 + 38 + 2 + 6 + 1 + 600 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 438327322 + ... + 438330278.

It is an arithmetic number, because the mean of its divisors is an integer number (5032386240).

Almost surely, 2^{1296138261600} is an apocalyptic number.

1296138261600 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 1296138261600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2898654474240).

1296138261600 is an abundant number, since it is smaller than the sum of its proper divisors (4501170686880).

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

1296138261600 is a wasteful number, since it uses less digits than its factorization.

1296138261600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3229 (or 3210 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The spelling of 1296138261600 in words is "one trillion, two hundred ninety-six billion, one hundred thirty-eight million, two hundred sixty-one thousand, six hundred".