161257140 has 144 divisors (see below), whose sum is σ = 556972416. Its totient is φ = 37382400.

The previous prime is 161257127. The next prime is 161257147. The reversal of 161257140 is 41752161.

It is a happy number.

161257140 is a `hidden beast` number, since 1 + 612 + 5 + 7 + 1 + 40 = 666.

161257140 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161257147) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 43770 + ... + 47310.

It is an arithmetic number, because the mean of its divisors is an integer number (3867864).

Almost surely, 2^161257140 is an apocalyptic number.

161257140 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 161257140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (278486208).

161257140 is an abundant number, since it is smaller than the sum of its proper divisors (395715276).

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

161257140 is a wasteful number, since it uses less digits than its factorization.

161257140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3590 (or 3585 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 27.

The square root of 161257140 is about 12698.7062333137. The cubic root of 161257140 is about 544.3016502129.

The spelling of 161257140 in words is "one hundred sixty-one million, two hundred fifty-seven thousand, one hundred forty".