261551967 has 16 divisors (see below), whose sum is σ = 367704960. Its totient is φ = 164914272.

The previous prime is 261551959. The next prime is 261551981. The reversal of 261551967 is 769155162.

It is not a de Polignac number, because 261551967 - 2³ = 261551959 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261551567) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 33708 + ... + 40734.

It is an arithmetic number, because the mean of its divisors is an integer number (22981560).

Almost surely, 2^261551967 is an apocalyptic number.

261551967 is a deficient number, since it is larger than the sum of its proper divisors (106152993).

261551967 is a wasteful number, since it uses less digits than its factorization.

261551967 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7702.

The product of its digits is 113400, while the sum is 42.

The square root of 261551967 is about 16172.5683489049. The cubic root of 261551967 is about 639.5178391539.

The spelling of 261551967 in words is "two hundred sixty-one million, five hundred fifty-one thousand, nine hundred sixty-seven".