661600260 has 72 divisors (see below), whose sum is σ = 2025668736. Its totient is φ = 174772800.

The previous prime is 661600253. The next prime is 661600297. The reversal of 661600260 is 62006166.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2085 + ... + 36435.

It is an arithmetic number, because the mean of its divisors is an integer number (28134288).

Almost surely, 2^661600260 is an apocalyptic number.

661600260 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 661600260, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1012834368).

661600260 is an abundant number, since it is smaller than the sum of its proper divisors (1364068476).

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

661600260 is a wasteful number, since it uses less digits than its factorization.

661600260 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34473 (or 34468 counting only the distinct ones).

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

The square root of 661600260 is about 25721.5913193566. The cubic root of 661600260 is about 871.3618781326.

The spelling of 661600260 in words is "six hundred sixty-one million, six hundred thousand, two hundred sixty".