201661560 has 48 divisors (see below), whose sum is σ = 655401240. Its totient is φ = 53776320.

The previous prime is 201661553. The next prime is 201661567. The reversal of 201661560 is 65166102.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (201661553) and next prime (201661567).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201661567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 279726 + ... + 280445.

Almost surely, 2^201661560 is an apocalyptic number.

201661560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

201661560 is an abundant number, since it is smaller than the sum of its proper divisors (453739680).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

201661560 is a wasteful number, since it uses less digits than its factorization.

201661560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 560188 (or 560181 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 201661560 is about 14200.7591346378. The cubic root of 201661560 is about 586.4185604352.

The spelling of 201661560 in words is "two hundred one million, six hundred sixty-one thousand, five hundred sixty".