261402555 has 8 divisors (see below), whose sum is σ = 418244112. Its totient is φ = 139414688.

The previous prime is 261402529. The next prime is 261402569. The reversal of 261402555 is 555204162.

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 261402555 - 2¹⁴ = 261386171 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8713404 + ... + 8713433.

It is an arithmetic number, because the mean of its divisors is an integer number (52280514).

Almost surely, 2^261402555 is an apocalyptic number.

261402555 is a deficient number, since it is larger than the sum of its proper divisors (156841557).

261402555 is a wasteful number, since it uses less digits than its factorization.

261402555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17426845.

The product of its (nonzero) digits is 12000, while the sum is 30.

The square root of 261402555 is about 16167.9483856178. The cubic root of 261402555 is about 639.3960407455.

The spelling of 261402555 in words is "two hundred sixty-one million, four hundred two thousand, five hundred fifty-five".