261932389 has 2 divisors, whose sum is σ = 261932390. Its totient is φ = 261932388.

The previous prime is 261932383. The next prime is 261932401. The reversal of 261932389 is 983239162.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 207792225 + 54140164 = 14415^2 + 7358^2 .

It is a cyclic number.

It is not a de Polignac number, because 261932389 - 2¹¹ = 261930341 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261932383) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130966194 + 130966195.

It is an arithmetic number, because the mean of its divisors is an integer number (130966195).

Almost surely, 2^261932389 is an apocalyptic number.

It is an amenable number.

261932389 is a deficient number, since it is larger than the sum of its proper divisors (1).

261932389 is an equidigital number, since it uses as much as digits as its factorization.

261932389 is an evil number, because the sum of its binary digits is even.

The product of its digits is 139968, while the sum is 43.

The square root of 261932389 is about 16184.3254107176. The cubic root of 261932389 is about 639.8277441689.

It can be divided in two parts, 26193 and 2389, that added together give a palindrome (28582).

The spelling of 261932389 in words is "two hundred sixty-one million, nine hundred thirty-two thousand, three hundred eighty-nine".