261173201 has 2 divisors, whose sum is σ = 261173202. Its totient is φ = 261173200.

The previous prime is 261173191. The next prime is 261173203. The reversal of 261173201 is 102371162.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 238857025 + 22316176 = 15455^2 + 4724^2 .

It is a cyclic number.

It is not a de Polignac number, because 261173201 - 2¹⁴ = 261156817 is a prime.

It is a super-2 number, since 2×261173201² = 136422881841172802, which contains 22 as substring.

Together with 261173203, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (261173203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130586600 + 130586601.

It is an arithmetic number, because the mean of its divisors is an integer number (130586601).

Almost surely, 2^261173201 is an apocalyptic number.

It is an amenable number.

261173201 is a deficient number, since it is larger than the sum of its proper divisors (1).

261173201 is an equidigital number, since it uses as much as digits as its factorization.

261173201 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 504, while the sum is 23.

The square root of 261173201 is about 16160.8539687728. The cubic root of 261173201 is about 639.2089844892.

The spelling of 261173201 in words is "two hundred sixty-one million, one hundred seventy-three thousand, two hundred one".