261293783607677 has 4 divisors (see below), whose sum is σ = 261897233454780. Its totient is φ = 260690333760576.

The previous prime is 261293783607673. The next prime is 261293783607691. The reversal of 261293783607677 is 776706387392162.

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

It can be written as a sum of positive squares in 2 ways, for example, as 120843102893956 + 140450680713721 = 10992866^2 + 11851189^2 .

It is a cyclic number.

It is not a de Polignac number, because 261293783607677 - 2² = 261293783607673 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 (261293783607673) 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, 301724922902 + ... + 301724923767.

It is an arithmetic number, because the mean of its divisors is an integer number (65474308363695).

Almost surely, 2^{261293783607677} is an apocalyptic number.

It is an amenable number.

261293783607677 is a deficient number, since it is larger than the sum of its proper divisors (603449847103).

261293783607677 is an equidigital number, since it uses as much as digits as its factorization.

261293783607677 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 603449847102.

The product of its (nonzero) digits is 1344252672, while the sum is 74.

The spelling of 261293783607677 in words is "two hundred sixty-one trillion, two hundred ninety-three billion, seven hundred eighty-three million, six hundred seven thousand, six hundred seventy-seven".