161532001 has 4 divisors (see below), whose sum is σ = 167102100. Its totient is φ = 155961904.

The previous prime is 161531983. The next prime is 161532043. The reversal of 161532001 is 100235161.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 99500625 + 62031376 = 9975^2 + 7876^2 .

It is a cyclic number.

It is not a de Polignac number, because 161532001 - 2⁷ = 161531873 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 161532001.

It is not an unprimeable number, because it can be changed into a prime (161532071) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2785006 + ... + 2785063.

It is an arithmetic number, because the mean of its divisors is an integer number (41775525).

Almost surely, 2^161532001 is an apocalyptic number.

It is an amenable number.

161532001 is a deficient number, since it is larger than the sum of its proper divisors (5570099).

161532001 is an equidigital number, since it uses as much as digits as its factorization.

161532001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5570098.

The product of its (nonzero) digits is 180, while the sum is 19.

The square root of 161532001 is about 12709.5240272797. The cubic root of 161532001 is about 544.6107267081.

Adding to 161532001 its reverse (100235161), we get a palindrome (261767162).

The spelling of 161532001 in words is "one hundred sixty-one million, five hundred thirty-two thousand, one".