1661151840750 has 256 divisors, whose sum is σ = 5005841817600. Its totient is φ = 406121040000.

The previous prime is 1661151840743. The next prime is 1661151840791. The reversal of 1661151840750 is 570481511661.

1661151840750 is a `hidden beast` number, since 1 + 6 + 61 + 1 + 518 + 4 + 0 + 75 + 0 = 666.

It is a super-2 number, since 2×1661151840750² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a junction number, because it is equal to n+sod(n) for n = 1661151840696 and 1661151840705.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 3766840 + ... + 4184660.

It is an arithmetic number, because the mean of its divisors is an integer number (19554069600).

Almost surely, 2^{1661151840750} is an apocalyptic number.

1661151840750 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1661151840750, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2502920908800).

1661151840750 is an abundant number, since it is smaller than the sum of its proper divisors (3344689976850).

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

1661151840750 is a wasteful number, since it uses less digits than its factorization.

1661151840750 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 417897 (or 417881 counting only the distinct ones).

The product of its (nonzero) digits is 201600, while the sum is 45.

The spelling of 1661151840750 in words is "one trillion, six hundred sixty-one billion, one hundred fifty-one million, eight hundred forty thousand, seven hundred fifty".