1661829400 has 288 divisors, whose sum is σ = 5058247680. Its totient is φ = 492768000.

The previous prime is 1661829397. The next prime is 1661829439. The reversal of 1661829400 is 49281661.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 1661829400.

It is a congruent number.

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 71 ways as a sum of consecutive naturals, for example, 28166571 + ... + 28166629.

It is an arithmetic number, because the mean of its divisors is an integer number (17563360).

Almost surely, 2^1661829400 is an apocalyptic number.

1661829400 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 1661829400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2529123840).

1661829400 is an abundant number, since it is smaller than the sum of its proper divisors (3396418280).

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

1661829400 is a wasteful number, since it uses less digits than its factorization.

1661829400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 183 (or 115 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 1661829400 is about 40765.5418214943. The cubic root of 1661829400 is about 1184.4829472323.

The spelling of 1661829400 in words is "one billion, six hundred sixty-one million, eight hundred twenty-nine thousand, four hundred".