261220697 has 2 divisors, whose sum is σ = 261220698. Its totient is φ = 261220696.

The previous prime is 261220693. The next prime is 261220747. The reversal of 261220697 is 796022162.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 213043216 + 48177481 = 14596^2 + 6941^2 .

It is a cyclic number.

It is not a de Polignac number, because 261220697 - 2² = 261220693 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (261220693) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130610348 + 130610349.

It is an arithmetic number, because the mean of its divisors is an integer number (130610349).

Almost surely, 2^261220697 is an apocalyptic number.

It is an amenable number.

261220697 is a deficient number, since it is larger than the sum of its proper divisors (1).

261220697 is an equidigital number, since it uses as much as digits as its factorization.

261220697 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18144, while the sum is 35.

The square root of 261220697 is about 16162.3233787720. The cubic root of 261220697 is about 639.2477302074.

The spelling of 261220697 in words is "two hundred sixty-one million, two hundred twenty thousand, six hundred ninety-seven".