1261610000 has 200 divisors, whose sum is σ = 3556111680. Its totient is φ = 424512000.

The previous prime is 1261609963. The next prime is 1261610011. The reversal of 1261610000 is 161621.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (200).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 4689866 + ... + 4690134.

Almost surely, 2^1261610000 is an apocalyptic number.

1261610000 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 1261610000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1778055840).

1261610000 is an abundant number, since it is smaller than the sum of its proper divisors (2294501680).

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

1261610000 is an equidigital number, since it uses as much as digits as its factorization.

1261610000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 371 (or 350 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 17.

The square root of 1261610000 is about 35519.1497645988. The cubic root of 1261610000 is about 1080.5421375064.

Adding to 1261610000 its reverse (161621), we get a palindrome (1261771621).

The spelling of 1261610000 in words is "one billion, two hundred sixty-one million, six hundred ten thousand".