261304981 has 8 divisors (see below), whose sum is σ = 298831680. Its totient is φ = 223827648.

The previous prime is 261304951. The next prime is 261304987. The reversal of 261304981 is 189403162.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261304981 is a prime.

It is a super-2 number, since 2×261304981² = 136560586190820722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261304987) 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, 196 + ... + 22861.

It is an arithmetic number, because the mean of its divisors is an integer number (37353960).

Almost surely, 2^261304981 is an apocalyptic number.

It is an amenable number.

261304981 is a deficient number, since it is larger than the sum of its proper divisors (37526699).

261304981 is a wasteful number, since it uses less digits than its factorization.

261304981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24683.

The product of its (nonzero) digits is 10368, while the sum is 34.

The square root of 261304981 is about 16164.9305906335. The cubic root of 261304981 is about 639.3164748393.

The spelling of 261304981 in words is "two hundred sixty-one million, three hundred four thousand, nine hundred eighty-one".