161211001 has 16 divisors (see below), whose sum is σ = 188293248. Its totient is φ = 135158400.

The previous prime is 161210947. The next prime is 161211007. The reversal of 161211001 is 100112161.

It is a cyclic number.

It is not a de Polignac number, because 161211001 - 2⁷ = 161210873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161211007) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 211461 + ... + 212221.

It is an arithmetic number, because the mean of its divisors is an integer number (11768328).

Almost surely, 2^161211001 is an apocalyptic number.

It is an amenable number.

161211001 is a deficient number, since it is larger than the sum of its proper divisors (27082247).

161211001 is an equidigital number, since it uses as much as digits as its factorization.

161211001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1392.

The product of its (nonzero) digits is 12, while the sum is 13.

The square root of 161211001 is about 12696.8894222168. The cubic root of 161211001 is about 544.2497332779.

Adding to 161211001 its reverse (100112161), we get a palindrome (261323162).

The spelling of 161211001 in words is "one hundred sixty-one million, two hundred eleven thousand, one".