261362889 has 16 divisors (see below), whose sum is σ = 392108800. Its totient is φ = 172034928.

The previous prime is 261362833. The next prime is 261362897. The reversal of 261362889 is 988263162.

261362889 is a `hidden beast` number, since 2 + 6 + 13 + 628 + 8 + 9 = 666.

It is not a de Polignac number, because 261362889 - 2¹⁶ = 261297353 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (261362089) 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 15 ways as a sum of consecutive naturals, for example, 59134 + ... + 63399.

It is an arithmetic number, because the mean of its divisors is an integer number (24506800).

Almost surely, 2^261362889 is an apocalyptic number.

It is an amenable number.

261362889 is a deficient number, since it is larger than the sum of its proper divisors (130745911).

261362889 is a wasteful number, since it uses less digits than its factorization.

261362889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122621 (or 122615 counting only the distinct ones).

The product of its digits is 248832, while the sum is 45.

The square root of 261362889 is about 16166.7216528275. The cubic root of 261362889 is about 639.3636978248.

The spelling of 261362889 in words is "two hundred sixty-one million, three hundred sixty-two thousand, eight hundred eighty-nine".