1201280661 has 24 divisors (see below), whose sum is σ = 2025264384. Its totient is φ = 671839200.

The previous prime is 1201280629. The next prime is 1201280671. The reversal of 1201280661 is 1660821021.

It is not a de Polignac number, because 1201280661 - 2⁵ = 1201280629 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1201280621) 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, 199890 + ... + 205811.

It is an arithmetic number, because the mean of its divisors is an integer number (84386016).

Almost surely, 2^1201280661 is an apocalyptic number.

It is an amenable number.

1201280661 is a deficient number, since it is larger than the sum of its proper divisors (823983723).

1201280661 is a wasteful number, since it uses less digits than its factorization.

1201280661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 405761 (or 405758 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 1201280661 is about 34659.4959715227. The cubic root of 1201280661 is about 1063.0364640563.

The spelling of 1201280661 in words is "one billion, two hundred one million, two hundred eighty thousand, six hundred sixty-one".