261158331 has 8 divisors (see below), whose sum is σ = 397955584. Its totient is φ = 149233320.

The previous prime is 261158329. The next prime is 261158333. The reversal of 261158331 is 133851162.

It is an interprime number because it is at equal distance from previous prime (261158329) and next prime (261158333).

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

It is not a de Polignac number, because 261158331 - 2¹ = 261158329 is a prime.

It is a super-2 number, since 2×261158331² = 136407347701411122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261158333) 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, 6218035 + ... + 6218076.

It is an arithmetic number, because the mean of its divisors is an integer number (49744448).

Almost surely, 2^261158331 is an apocalyptic number.

261158331 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

261158331 is a deficient number, since it is larger than the sum of its proper divisors (136797253).

261158331 is a wasteful number, since it uses less digits than its factorization.

261158331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12436121.

The product of its digits is 4320, while the sum is 30.

The square root of 261158331 is about 16160.3938999023. The cubic root of 261158331 is about 639.1968530531.

The spelling of 261158331 in words is "two hundred sixty-one million, one hundred fifty-eight thousand, three hundred thirty-one".