661298848704 has 896 divisors, whose sum is σ = 2239767936000. Its totient is φ = 189885136896.

The previous prime is 661298848703. The next prime is 661298848741. The reversal of 661298848704 is 407848892166.

661298848704 is a `hidden beast` number, since 6 + 61 + 2 + 98 + 8 + 487 + 0 + 4 = 666.

It is a super-3 number, since 3×661298848704³ (a number of 36 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661298848703) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 3694406887 + ... + 3694407065.

It is an arithmetic number, because the mean of its divisors is an integer number (2499741000).

Almost surely, 2^661298848704 is an apocalyptic number.

661298848704 is a gapful number since it is divisible by the number (64) 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 661298848704, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1119883968000).

661298848704 is an abundant number, since it is smaller than the sum of its proper divisors (1578469087296).

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

661298848704 is a wasteful number, since it uses less digits than its factorization.

661298848704 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 402 (or 386 counting only the distinct ones).

The product of its (nonzero) digits is 37158912, while the sum is 63.

The spelling of 661298848704 in words is "six hundred sixty-one billion, two hundred ninety-eight million, eight hundred forty-eight thousand, seven hundred four".