201664641 has 8 divisors (see below), whose sum is σ = 277560064. Its totient is φ = 130106160.

The previous prime is 201664633. The next prime is 201664663. The reversal of 201664641 is 146466102.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 201664641 - 2³ = 201664633 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 201664599 and 201664608.

It is not an unprimeable number, because it can be changed into a prime (201664601) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1084126 + ... + 1084311.

It is an arithmetic number, because the mean of its divisors is an integer number (34695008).

Almost surely, 2^201664641 is an apocalyptic number.

It is an amenable number.

201664641 is a deficient number, since it is larger than the sum of its proper divisors (75895423).

201664641 is a wasteful number, since it uses less digits than its factorization.

201664641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2168471.

The product of its (nonzero) digits is 6912, while the sum is 30.

The square root of 201664641 is about 14200.8676143396. The cubic root of 201664641 is about 586.4215468685.

It can be divided in two parts, 20 and 1664641, that added together give a palindrome (1664661).

The spelling of 201664641 in words is "two hundred one million, six hundred sixty-four thousand, six hundred forty-one".