201664971 has 24 divisors (see below), whose sum is σ = 302760640. Its totient is φ = 134141832.

The previous prime is 201664907. The next prime is 201664973. The reversal of 201664971 is 179466102.

201664971 is a `hidden beast` number, since 2 + 0 + 1 + 6 + 649 + 7 + 1 = 666.

It is not a de Polignac number, because 201664971 - 2⁶ = 201664907 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (201664973) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 179016 + ... + 180138.

Almost surely, 2^201664971 is an apocalyptic number.

201664971 is a deficient number, since it is larger than the sum of its proper divisors (101095669).

201664971 is an equidigital number, since it uses as much as digits as its factorization.

201664971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1877 (or 1865 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 201664971 is about 14200.8792333433. The cubic root of 201664971 is about 586.4218667379.

The spelling of 201664971 in words is "two hundred one million, six hundred sixty-four thousand, nine hundred seventy-one".