161995680 has 384 divisors, whose sum is σ = 708341760. Its totient is φ = 33592320.

The previous prime is 161995667. The next prime is 161995681. The reversal of 161995680 is 86599161.

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

It is not an unprimeable number, because it can be changed into a prime (161995681) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 332397 + ... + 332883.

It is an arithmetic number, because the mean of its divisors is an integer number (1844640).

Almost surely, 2^161995680 is an apocalyptic number.

161995680 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 161995680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (354170880).

161995680 is an abundant number, since it is smaller than the sum of its proper divisors (546346080).

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

161995680 is a wasteful number, since it uses less digits than its factorization.

161995680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 529 (or 515 counting only the distinct ones).

The product of its (nonzero) digits is 116640, while the sum is 45.

The square root of 161995680 is about 12727.7523545990. The cubic root of 161995680 is about 545.1313321517.

The spelling of 161995680 in words is "one hundred sixty-one million, nine hundred ninety-five thousand, six hundred eighty".