1661603129200 has 60 divisors (see below), whose sum is σ = 4562287456720. Its totient is φ = 569692500480.

The previous prime is 1661603129189. The next prime is 1661603129239. The reversal of 1661603129200 is 29213061661.

It is a super-4 number, since 4×1661603129200⁴ (a number of 50 digits) contains 4444 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1661603129200.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 296712045 + ... + 296717644.

Almost surely, 2^{1661603129200} is an apocalyptic number.

1661603129200 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1661603129200 is an abundant number, since it is smaller than the sum of its proper divisors (2900684327520).

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

1661603129200 is a wasteful number, since it uses less digits than its factorization.

1661603129200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 593429714 (or 593429703 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 37.

The spelling of 1661603129200 in words is "one trillion, six hundred sixty-one billion, six hundred three million, one hundred twenty-nine thousand, two hundred".