161901686400 has 192 divisors, whose sum is σ = 543326965920. Its totient is φ = 42359050240.

The previous prime is 161901686369. The next prime is 161901686437. The reversal of 161901686400 is 4686109161.

It is a tau number, because it is divible by the number of its divisors (192).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 349699 + ... + 667901.

Almost surely, 2^161901686400 is an apocalyptic number.

161901686400 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 161901686400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (271663482960).

161901686400 is an abundant number, since it is smaller than the sum of its proper divisors (381425279520).

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

161901686400 is a wasteful number, since it uses less digits than its factorization.

161901686400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 318283 (or 318266 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 42.

The spelling of 161901686400 in words is "one hundred sixty-one billion, nine hundred one million, six hundred eighty-six thousand, four hundred".