261139078 has 8 divisors (see below), whose sum is σ = 412324920. Its totient is φ = 123697440.

The previous prime is 261139049. The next prime is 261139103. The reversal of 261139078 is 870931162.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3436003 + ... + 3436078.

It is an arithmetic number, because the mean of its divisors is an integer number (51540615).

Almost surely, 2^261139078 is an apocalyptic number.

261139078 is a deficient number, since it is larger than the sum of its proper divisors (151185842).

261139078 is a wasteful number, since it uses less digits than its factorization.

261139078 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6872102.

The product of its (nonzero) digits is 18144, while the sum is 37.

The square root of 261139078 is about 16159.7982041856. The cubic root of 261139078 is about 639.1811451370.

The spelling of 261139078 in words is "two hundred sixty-one million, one hundred thirty-nine thousand, seventy-eight".