161257530 has 96 divisors (see below), whose sum is σ = 453639744. Its totient is φ = 36578304.

The previous prime is 161257513. The next prime is 161257549. The reversal of 161257530 is 35752161.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 239274 + ... + 239946.

It is an arithmetic number, because the mean of its divisors is an integer number (4725414).

Almost surely, 2^161257530 is an apocalyptic number.

161257530 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 161257530, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (226819872).

161257530 is an abundant number, since it is smaller than the sum of its proper divisors (292382214).

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

161257530 is a wasteful number, since it uses less digits than its factorization.

161257530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 860 (or 853 counting only the distinct ones).

The product of its (nonzero) digits is 6300, while the sum is 30.

The square root of 161257530 is about 12698.7215891994. The cubic root of 161257530 is about 544.3020890100.

The spelling of 161257530 in words is "one hundred sixty-one million, two hundred fifty-seven thousand, five hundred thirty".