961649281 has 4 divisors (see below), whose sum is σ = 982109952. Its totient is φ = 941188612.

The previous prime is 961649279. The next prime is 961649317. The reversal of 961649281 is 182946169.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 182946169 = 7 ⋅26135167.

It is a cyclic number.

It is not a de Polignac number, because 961649281 - 2¹ = 961649279 is a prime.

It is a super-2 number, since 2×961649281² = 1849538679295633922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (961949281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10230265 + ... + 10230358.

It is an arithmetic number, because the mean of its divisors is an integer number (245527488).

Almost surely, 2^961649281 is an apocalyptic number.

It is an amenable number.

961649281 is a deficient number, since it is larger than the sum of its proper divisors (20460671).

961649281 is a wasteful number, since it uses less digits than its factorization.

961649281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20460670.

The product of its digits is 186624, while the sum is 46.

The square root of 961649281 is about 31010.4705059436. The cubic root of 961649281 is about 987.0494338471.

The spelling of 961649281 in words is "nine hundred sixty-one million, six hundred forty-nine thousand, two hundred eighty-one".