249779722261 has 2 divisors, whose sum is σ = 249779722262. Its totient is φ = 249779722260.

The previous prime is 249779722139. The next prime is 249779722351. The reversal of 249779722261 is 162227977942.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 150936135025 + 98843587236 = 388505^2 + 314394^2 .

It is a cyclic number.

It is not a de Polignac number, because 249779722261 - 2⁷ = 249779722133 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 249779722196 and 249779722205.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (249779722561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 124889861130 + 124889861131.

It is an arithmetic number, because the mean of its divisors is an integer number (124889861131).

Almost surely, 2^249779722261 is an apocalyptic number.

It is an amenable number.

249779722261 is a deficient number, since it is larger than the sum of its proper divisors (1).

249779722261 is an equidigital number, since it uses as much as digits as its factorization.

249779722261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10668672, while the sum is 58.

The spelling of 249779722261 in words is "two hundred forty-nine billion, seven hundred seventy-nine million, seven hundred twenty-two thousand, two hundred sixty-one".