180020001901 has 4 divisors (see below), whose sum is σ = 180085681404. Its totient is φ = 179954322400.

The previous prime is 180020001883. The next prime is 180020001949. The reversal of 180020001901 is 109100020081.

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 90694334025 + 89325667876 = 301155^2 + 298874^2 .

It is a cyclic number.

It is not a de Polignac number, because 180020001901 - 2²⁵ = 179986447469 is a prime.

It is a super-2 number, since 2×180020001901² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (180020001991) 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, 32835640 + ... + 32841121.

It is an arithmetic number, because the mean of its divisors is an integer number (45021420351).

Almost surely, 2^180020001901 is an apocalyptic number.

It is an amenable number.

180020001901 is a deficient number, since it is larger than the sum of its proper divisors (65679503).

180020001901 is an equidigital number, since it uses as much as digits as its factorization.

180020001901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65679502.

The product of its (nonzero) digits is 144, while the sum is 22.

Adding to 180020001901 its reverse (109100020081), we get a palindrome (289120021982).

The spelling of 180020001901 in words is "one hundred eighty billion, twenty million, one thousand, nine hundred one".