201660561652 has 18 divisors (see below), whose sum is σ = 387904924274. Its totient is φ = 91663891440.

The previous prime is 201660561593. The next prime is 201660561673. The reversal of 201660561652 is 256165066102.

It can be written as a sum of positive squares in only one way, i.e., 119574873616 + 82085688036 = 345796^2 + 286506^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 208326543 + ... + 208327510.

Almost surely, 2^201660561652 is an apocalyptic number.

201660561652 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

201660561652 is a deficient number, since it is larger than the sum of its proper divisors (186244362622).

201660561652 is a wasteful number, since it uses less digits than its factorization.

201660561652 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 416654079 (or 416654066 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 40.

The spelling of 201660561652 in words is "two hundred one billion, six hundred sixty million, five hundred sixty-one thousand, six hundred fifty-two".