261078799 has 4 divisors (see below), whose sum is σ = 261461736. Its totient is φ = 260695864.

The previous prime is 261078787. The next prime is 261078817. The reversal of 261078799 is 997870162.

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 261078799 - 2⁵ = 261078767 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261078709) 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, 190444 + ... + 191809.

It is an arithmetic number, because the mean of its divisors is an integer number (65365434).

Almost surely, 2^261078799 is an apocalyptic number.

261078799 is a deficient number, since it is larger than the sum of its proper divisors (382937).

261078799 is an equidigital number, since it uses as much as digits as its factorization.

261078799 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 382936.

The product of its (nonzero) digits is 381024, while the sum is 49.

The square root of 261078799 is about 16157.9330051836. The cubic root of 261078799 is about 639.1319604069.

The spelling of 261078799 in words is "two hundred sixty-one million, seventy-eight thousand, seven hundred ninety-nine".