261463641 has 16 divisors (see below), whose sum is σ = 363179520. Its totient is φ = 167132160.

The previous prime is 261463639. The next prime is 261463661. The reversal of 261463641 is 146364162.

It is not a de Polignac number, because 261463641 - 2¹ = 261463639 is a prime.

It is not an unprimeable number, because it can be changed into a prime (261463661) 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, 2760 + ... + 23033.

It is an arithmetic number, because the mean of its divisors is an integer number (22698720).

Almost surely, 2^261463641 is an apocalyptic number.

It is an amenable number.

261463641 is a deficient number, since it is larger than the sum of its proper divisors (101715879).

261463641 is a wasteful number, since it uses less digits than its factorization.

261463641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25936.

The product of its digits is 20736, while the sum is 33.

The square root of 261463641 is about 16169.8373832268. The cubic root of 261463641 is about 639.4458427383.

The spelling of 261463641 in words is "two hundred sixty-one million, four hundred sixty-three thousand, six hundred forty-one".