161540742 has 64 divisors (see below), whose sum is σ = 366799104. Its totient is φ = 46995840.

The previous prime is 161540741. The next prime is 161540773. The reversal of 161540742 is 247045161.

It is a super-2 number, since 2×161540742² = 52190822651821128, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161540741) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 202288 + ... + 203084.

It is an arithmetic number, because the mean of its divisors is an integer number (5731236).

Almost surely, 2^161540742 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161540742, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (183399552).

161540742 is an abundant number, since it is smaller than the sum of its proper divisors (205258362).

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

161540742 is a wasteful number, since it uses less digits than its factorization.

161540742 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 933.

The product of its (nonzero) digits is 6720, while the sum is 30.

The square root of 161540742 is about 12709.8678986054. The cubic root of 161540742 is about 544.6205500588.

The spelling of 161540742 in words is "one hundred sixty-one million, five hundred forty thousand, seven hundred forty-two".