661056201 has 16 divisors (see below), whose sum is σ = 1054677120. Its totient is φ = 406803600.

The previous prime is 661056049. The next prime is 661056223. The reversal of 661056201 is 102650166.

It is a happy number.

It is not a de Polignac number, because 661056201 - 2²² = 656861897 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (661056241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 941325 + ... + 942026.

It is an arithmetic number, because the mean of its divisors is an integer number (65917320).

Almost surely, 2^661056201 is an apocalyptic number.

It is an amenable number.

661056201 is a deficient number, since it is larger than the sum of its proper divisors (393620919).

661056201 is a wasteful number, since it uses less digits than its factorization.

661056201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1883373 (or 1883367 counting only the distinct ones).

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

The square root of 661056201 is about 25711.0132239085. The cubic root of 661056201 is about 871.1229613176.

The spelling of 661056201 in words is "six hundred sixty-one million, fifty-six thousand, two hundred one".