261227977 has 2 divisors, whose sum is σ = 261227978. Its totient is φ = 261227976.

The previous prime is 261227963. The next prime is 261228101. The reversal of 261227977 is 779722162.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 185259321 + 75968656 = 13611^2 + 8716^2 .

It is a cyclic number.

It is not a de Polignac number, because 261227977 - 2⁷ = 261227849 is a prime.

It is not a weakly prime, because it can be changed into another prime (261227177) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130613988 + 130613989.

It is an arithmetic number, because the mean of its divisors is an integer number (130613989).

Almost surely, 2^261227977 is an apocalyptic number.

It is an amenable number.

261227977 is a deficient number, since it is larger than the sum of its proper divisors (1).

261227977 is an equidigital number, since it uses as much as digits as its factorization.

261227977 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 148176, while the sum is 43.

The square root of 261227977 is about 16162.5485923477. The cubic root of 261227977 is about 639.2536685835.

The spelling of 261227977 in words is "two hundred sixty-one million, two hundred twenty-seven thousand, nine hundred seventy-seven".