261301993 has 2 divisors, whose sum is σ = 261301994. Its totient is φ = 261301992.

The previous prime is 261301987. The next prime is 261302009. The reversal of 261301993 is 399103162.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 184090624 + 77211369 = 13568^2 + 8787^2 .

It is a cyclic number.

It is not a de Polignac number, because 261301993 - 2¹³ = 261293801 is a prime.

It is not a weakly prime, because it can be changed into another prime (261301913) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130650996 + 130650997.

It is an arithmetic number, because the mean of its divisors is an integer number (130650997).

Almost surely, 2^261301993 is an apocalyptic number.

It is an amenable number.

261301993 is a deficient number, since it is larger than the sum of its proper divisors (1).

261301993 is an equidigital number, since it uses as much as digits as its factorization.

261301993 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8748, while the sum is 34.

The square root of 261301993 is about 16164.8381680733. The cubic root of 261301993 is about 639.3140379871.

The spelling of 261301993 in words is "two hundred sixty-one million, three hundred one thousand, nine hundred ninety-three".