261478023 has 4 divisors (see below), whose sum is σ = 348637368. Its totient is φ = 174318680.

The previous prime is 261477989. The next prime is 261478067. The reversal of 261478023 is 320874162.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261478023 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261474023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 43579668 + ... + 43579673.

It is an arithmetic number, because the mean of its divisors is an integer number (87159342).

Almost surely, 2^261478023 is an apocalyptic number.

261478023 is a deficient number, since it is larger than the sum of its proper divisors (87159345).

261478023 is an equidigital number, since it uses as much as digits as its factorization.

261478023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87159344.

The product of its (nonzero) digits is 16128, while the sum is 33.

The square root of 261478023 is about 16170.2820940143. The cubic root of 261478023 is about 639.4575669198.

The spelling of 261478023 in words is "two hundred sixty-one million, four hundred seventy-eight thousand, twenty-three".