661494936960 has 2560 divisors, whose sum is σ = 3056688835200. Its totient is φ = 133772083200.

The previous prime is 661494936937. The next prime is 661494937027. The reversal of 661494936960 is 69639494166.

661494936960 is a `hidden beast` number, since 6 + 614 + 9 + 4 + 9 + 3 + 6 + 9 + 6 + 0 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 319 ways as a sum of consecutive naturals, for example, 3654668070 + ... + 3654668250.

Almost surely, 2^661494936960 is an apocalyptic number.

661494936960 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 661494936960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1528344417600).

661494936960 is an abundant number, since it is smaller than the sum of its proper divisors (2395193898240).

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

661494936960 is a wasteful number, since it uses less digits than its factorization.

661494936960 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 282 (or 261 counting only the distinct ones).

The product of its (nonzero) digits is 45349632, while the sum is 63.

The spelling of 661494936960 in words is "six hundred sixty-one billion, four hundred ninety-four million, nine hundred thirty-six thousand, nine hundred sixty".