661144750 has 96 divisors (see below), whose sum is σ = 1487026944. Its totient is φ = 219240000.

The previous prime is 661144747. The next prime is 661144751. The reversal of 661144750 is 57441166.

It is a super-2 number, since 2×661144750² = 874224760905125000, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661144751) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 378880 + ... + 380620.

It is an arithmetic number, because the mean of its divisors is an integer number (15489864).

Almost surely, 2^661144750 is an apocalyptic number.

661144750 is an abundant number, since it is smaller than the sum of its proper divisors (825882194).

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

661144750 is a wasteful number, since it uses less digits than its factorization.

661144750 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1803 (or 1786 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 34.

The square root of 661144750 is about 25712.7351715060. The cubic root of 661144750 is about 871.1618554505.

The spelling of 661144750 in words is "six hundred sixty-one million, one hundred forty-four thousand, seven hundred fifty".