5665661400 has 384 divisors, whose sum is σ = 21564334080. Its totient is φ = 1201029120.

The previous prime is 5665661387. The next prime is 5665661431. The reversal of 5665661400 is 41665665.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 5211657 + ... + 5212743.

It is an arithmetic number, because the mean of its divisors is an integer number (56157120).

Almost surely, 2^5665661400 is an apocalyptic number.

5665661400 is a gapful number since it is divisible by the number (50) 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 5665661400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10782167040).

5665661400 is an abundant number, since it is smaller than the sum of its proper divisors (15898672680).

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

5665661400 is a wasteful number, since it uses less digits than its factorization.

5665661400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1203 (or 1194 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 39.

The square root of 5665661400 is about 75270.5878813232. The cubic root of 5665661400 is about 1782.7216496704.

The spelling of 5665661400 in words is "five billion, six hundred sixty-five million, six hundred sixty-one thousand, four hundred".