161040253440 has 320 divisors, whose sum is σ = 562651702272. Its totient is φ = 38968934400.

The previous prime is 161040253369. The next prime is 161040253453. The reversal of 161040253440 is 44352040161.

It is a tau number, because it is divible by the number of its divisors (320).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 161040253398 and 161040253407.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 57698445 + ... + 57701235.

Almost surely, 2^161040253440 is an apocalyptic number.

161040253440 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 161040253440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (281325851136).

161040253440 is an abundant number, since it is smaller than the sum of its proper divisors (401611448832).

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

161040253440 is a wasteful number, since it uses less digits than its factorization.

161040253440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3511 (or 3495 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 30.

The spelling of 161040253440 in words is "one hundred sixty-one billion, forty million, two hundred fifty-three thousand, four hundred forty".