661107744 has 288 divisors, whose sum is σ = 2179457280. Its totient is φ = 195436800.

The previous prime is 661107737. The next prime is 661107761. The reversal of 661107744 is 447701166.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 661107699 and 661107708.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5046559 + ... + 5046689.

It is an arithmetic number, because the mean of its divisors is an integer number (7567560).

Almost surely, 2^661107744 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 661107744, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1089728640).

661107744 is an abundant number, since it is smaller than the sum of its proper divisors (1518349536).

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

661107744 is a wasteful number, since it uses less digits than its factorization.

661107744 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226 (or 206 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 36.

The square root of 661107744 is about 25712.0155569337. The cubic root of 661107744 is about 871.1456014118.

The spelling of 661107744 in words is "six hundred sixty-one million, one hundred seven thousand, seven hundred forty-four".