261306087 has 8 divisors (see below), whose sum is σ = 398180736. Its totient is φ = 149317752.

The previous prime is 261306077. The next prime is 261306113. The reversal of 261306087 is 780603162.

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

It is not a de Polignac number, because 261306087 - 2¹¹ = 261304039 is a prime.

It is a super-2 number, since 2×261306087² = 136561742206503138, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261306007) 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, 6221553 + ... + 6221594.

It is an arithmetic number, because the mean of its divisors is an integer number (49772592).

Almost surely, 2^261306087 is an apocalyptic number.

261306087 is a deficient number, since it is larger than the sum of its proper divisors (136874649).

261306087 is a wasteful number, since it uses less digits than its factorization.

261306087 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12443157.

The product of its (nonzero) digits is 12096, while the sum is 33.

The square root of 261306087 is about 16164.9648004566. The cubic root of 261306087 is about 639.3173768288.

The spelling of 261306087 in words is "two hundred sixty-one million, three hundred six thousand, eighty-seven".