1261008000 has 640 divisors, whose sum is σ = 5390985600. Its totient is φ = 286156800.

The previous prime is 1261007911. The next prime is 1261008011. The reversal of 1261008000 is 8001621.

It is a tau number, because it is divible by the number of its divisors (640).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 9071931 + ... + 9072069.

It is an arithmetic number, because the mean of its divisors is an integer number (8423415).

Almost surely, 2^1261008000 is an apocalyptic number.

1261008000 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 1261008000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2695492800).

1261008000 is an abundant number, since it is smaller than the sum of its proper divisors (4129977600).

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

1261008000 is an equidigital number, since it uses as much as digits as its factorization.

1261008000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 187 (or 156 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

The square root of 1261008000 is about 35510.6744514942. The cubic root of 1261008000 is about 1080.3702434298.

Adding to 1261008000 its reverse (8001621), we get a palindrome (1269009621).

The spelling of 1261008000 in words is "one billion, two hundred sixty-one million, eight thousand".