661340160 has 480 divisors, whose sum is σ = 2642330880. Its totient is φ = 155713536.

The previous prime is 661340159. The next prime is 661340161. The reversal of 661340160 is 61043166.

661340160 is a `hidden beast` number, since 6 + 613 + 40 + 1 + 6 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (661340159) and next prime (661340161).

It is a tau number, because it is divible by the number of its divisors (480).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661340161) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 28753909 + ... + 28753931.

It is an arithmetic number, because the mean of its divisors is an integer number (5504856).

Almost surely, 2^661340160 is an apocalyptic number.

661340160 is a gapful number since it is divisible by the number (60) 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 661340160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1321165440).

661340160 is an abundant number, since it is smaller than the sum of its proper divisors (1980990720).

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

661340160 is a wasteful number, since it uses less digits than its factorization.

661340160 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78 (or 46 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 661340160 is about 25716.5347587889. The cubic root of 661340160 is about 871.2476747658.

The spelling of 661340160 in words is "six hundred sixty-one million, three hundred forty thousand, one hundred sixty".