261952381 has 8 divisors (see below), whose sum is σ = 264910464. Its totient is φ = 259002480.

The previous prime is 261952367. The next prime is 261952391. The reversal of 261952381 is 183259162.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 261952381 - 2⁵ = 261952349 is a prime.

It is a super-2 number, since 2×261952381² = 137238099823138322, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 261952381.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261952351) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 80496 + ... + 83686.

It is an arithmetic number, because the mean of its divisors is an integer number (33113808).

Almost surely, 2^261952381 is an apocalyptic number.

It is an amenable number.

261952381 is a deficient number, since it is larger than the sum of its proper divisors (2958083).

261952381 is a wasteful number, since it uses less digits than its factorization.

261952381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4091.

The product of its digits is 25920, while the sum is 37.

The square root of 261952381 is about 16184.9430335729. The cubic root of 261952381 is about 639.8440220474.

The spelling of 261952381 in words is "two hundred sixty-one million, nine hundred fifty-two thousand, three hundred eighty-one".