1661201300 has 72 divisors (see below), whose sum is σ = 3957975840. Its totient is φ = 600163200.

The previous prime is 1661201273. The next prime is 1661201341. The reversal of 1661201300 is 31021661.

1661201300 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 167891 + ... + 177509.

Almost surely, 2^1661201300 is an apocalyptic number.

1661201300 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 1661201300, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1978987920).

1661201300 is an abundant number, since it is smaller than the sum of its proper divisors (2296774540).

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

1661201300 is a wasteful number, since it uses less digits than its factorization.

1661201300 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9801 (or 9794 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 1661201300 is about 40757.8372831533. The cubic root of 1661201300 is about 1184.3337005670. Note that the first 3 decimals are identical.

Adding to 1661201300 its reverse (31021661), we get a palindrome (1692222961).

The spelling of 1661201300 in words is "one billion, six hundred sixty-one million, two hundred one thousand, three hundred".