261429587 has 4 divisors (see below), whose sum is σ = 276807816. Its totient is φ = 246051360.

The previous prime is 261429563. The next prime is 261429599. The reversal of 261429587 is 785924162.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 261429587 - 2²⁶ = 194320723 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261429517) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7689089 + ... + 7689122.

It is an arithmetic number, because the mean of its divisors is an integer number (69201954).

Almost surely, 2^261429587 is an apocalyptic number.

261429587 is a deficient number, since it is larger than the sum of its proper divisors (15378229).

261429587 is a wasteful number, since it uses less digits than its factorization.

261429587 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15378228.

The product of its digits is 241920, while the sum is 44.

The square root of 261429587 is about 16168.7843389662. The cubic root of 261429587 is about 639.4180802623.

The spelling of 261429587 in words is "two hundred sixty-one million, four hundred twenty-nine thousand, five hundred eighty-seven".