1661034117600 has 864 divisors, whose sum is σ = 6935940071424. Its totient is φ = 368744140800.

The previous prime is 1661034117577. The next prime is 1661034117623. The reversal of 1661034117600 is 67114301661.

1661034117600 is a `hidden beast` number, since 1 + 6 + 6 + 1 + 0 + 3 + 41 + 1 + 7 + 600 = 666.

It is an interprime number because it is at equal distance from previous prime (1661034117577) and next prime (1661034117623).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 130752849 + ... + 130765551.

It is an arithmetic number, because the mean of its divisors is an integer number (8027708416).

Almost surely, 2^{1661034117600} is an apocalyptic number.

1661034117600 is a gapful number since it is divisible by the number (10) 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 1661034117600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3467970035712).

1661034117600 is an abundant number, since it is smaller than the sum of its proper divisors (5274905953824).

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

1661034117600 is a wasteful number, since it uses less digits than its factorization.

1661034117600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12880 (or 12864 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The spelling of 1661034117600 in words is "one trillion, six hundred sixty-one billion, thirty-four million, one hundred seventeen thousand, six hundred".