161271265680 has 1440 divisors, whose sum is σ = 723540190464. Its totient is φ = 33108590592.

The previous prime is 161271265643. The next prime is 161271265691. The reversal of 161271265680 is 86562172161.

161271265680 is a `hidden beast` number, since 1 + 6 + 12 + 71 + 2 + 6 + 568 + 0 = 666.

It is a super-2 number, since 2×161271265680² (a number of 23 digits) contains 22 as substring.

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

It is an unprimeable number.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 372450744 + ... + 372451176.

Almost surely, 2^161271265680 is an apocalyptic number.

161271265680 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 161271265680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (361770095232).

161271265680 is an abundant number, since it is smaller than the sum of its proper divisors (562268924784).

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

161271265680 is a wasteful number, since it uses less digits than its factorization.

161271265680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 515 (or 490 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 45.

The spelling of 161271265680 in words is "one hundred sixty-one billion, two hundred seventy-one million, two hundred sixty-five thousand, six hundred eighty".