1261801008 has 120 divisors (see below), whose sum is σ = 3823921920. Its totient is φ = 386104320.

The previous prime is 1261801003. The next prime is 1261801027. The reversal of 1261801008 is 8001081621.

It is not an unprimeable number, because it can be changed into a prime (1261801003) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 355788 + ... + 359316.

It is an arithmetic number, because the mean of its divisors is an integer number (31866016).

Almost surely, 2^1261801008 is an apocalyptic number.

1261801008 is a gapful number since it is divisible by the number (18) 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 1261801008, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1911960960).

1261801008 is an abundant number, since it is smaller than the sum of its proper divisors (2562120912).

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

1261801008 is a wasteful number, since it uses less digits than its factorization.

1261801008 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3747 (or 3738 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 27.

The square root of 1261801008 is about 35521.8384659353. The cubic root of 1261801008 is about 1080.5966661847.

Adding to 1261801008 its reverse (8001081621), we get a palindrome (9262882629).

The spelling of 1261801008 in words is "one billion, two hundred sixty-one million, eight hundred one thousand, eight".