1213810000 has 100 divisors (see below), whose sum is σ = 3165152452. Its totient is φ = 448128000.

The previous prime is 1213809997. The next prime is 1213810007. The reversal of 1213810000 is 183121.

It can be written as a sum of positive squares in 10 ways, for example, as 843786304 + 370023696 = 29048^2 + 19236^2 .

It is a tau number, because it is divible by the number of its divisors (100).

It is a super-2 number, since 2×1213810000² = 2946669432200000000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1213810007) by changing a digit.

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 19 ways as a sum of consecutive naturals, for example, 125332 + ... + 134668.

Almost surely, 2^1213810000 is an apocalyptic number.

1213810000 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 1213810000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1582576226).

1213810000 is an abundant number, since it is smaller than the sum of its proper divisors (1951342452).

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

1213810000 is an equidigital number, since it uses as much as digits as its factorization.

1213810000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9378 (or 9357 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 16.

The square root of 1213810000 is about 34839.7761186837. The cubic root of 1213810000 is about 1066.7195069310.

Adding to 1213810000 its reverse (183121), we get a palindrome (1213993121).

The spelling of 1213810000 in words is "one billion, two hundred thirteen million, eight hundred ten thousand".