661453055542260 has 240 divisors, whose sum is σ = 2076633363974400. Its totient is φ = 176248909138176.

The previous prime is 661453055542229. The next prime is 661453055542261. The reversal of 661453055542260 is 62245550354166.

661453055542260 is a `hidden beast` number, since 6 + 6 + 1 + 4 + 5 + 3 + 0 + 5 + 554 + 22 + 60 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a junction number, because it is equal to n+sod(n) for n = 661453055542197 and 661453055542206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661453055542261) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 16771527621 + ... + 16771567059.

It is an arithmetic number, because the mean of its divisors is an integer number (8652639016560).

Almost surely, 2^{661453055542260} is an apocalyptic number.

661453055542260 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 661453055542260, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1038316681987200).

661453055542260 is an abundant number, since it is smaller than the sum of its proper divisors (1415180308432140).

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

661453055542260 is a wasteful number, since it uses less digits than its factorization.

661453055542260 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47332 (or 47321 counting only the distinct ones).

The product of its (nonzero) digits is 25920000, while the sum is 54.

The spelling of 661453055542260 in words is "six hundred sixty-one trillion, four hundred fifty-three billion, fifty-five million, five hundred forty-two thousand, two hundred sixty".