161577721578000 has 960 divisors, whose sum is σ = 654024390259968. Its totient is φ = 34016158310400.

The previous prime is 161577721577983. The next prime is 161577721578019. The reversal of 161577721578000 is 875127775161.

It is a super-2 number, since 2×161577721578000² (a number of 29 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 1746607747 + ... + 1746700253.

Almost surely, 2^{161577721578000} is an apocalyptic number.

161577721578000 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 161577721578000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (327012195129984).

161577721578000 is an abundant number, since it is smaller than the sum of its proper divisors (492446668681968).

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

161577721578000 is a wasteful number, since it uses less digits than its factorization.

161577721578000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93017 (or 92994 counting only the distinct ones).

The product of its (nonzero) digits is 5762400, while the sum is 57.

The spelling of 161577721578000 in words is "one hundred sixty-one trillion, five hundred seventy-seven billion, seven hundred twenty-one million, five hundred seventy-eight thousand".