161229809664 has 768 divisors, whose sum is σ = 627105024000. Its totient is φ = 39653867520.

The previous prime is 161229809659. The next prime is 161229809707. The reversal of 161229809664 is 466908922161.

It is a tau number, because it is divible by the number of its divisors (768).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 161229809664.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 80897052 + ... + 80899044.

It is an arithmetic number, because the mean of its divisors is an integer number (816543000).

Almost surely, 2^161229809664 is an apocalyptic number.

161229809664 is a gapful number since it is divisible by the number (14) 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 161229809664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (313552512000).

161229809664 is an abundant number, since it is smaller than the sum of its proper divisors (465875214336).

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

161229809664 is a wasteful number, since it uses less digits than its factorization.

161229809664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2061 (or 2035 counting only the distinct ones).

The product of its (nonzero) digits is 2239488, while the sum is 54.

The spelling of 161229809664 in words is "one hundred sixty-one billion, two hundred twenty-nine million, eight hundred nine thousand, six hundred sixty-four".