261011963 has 2 divisors, whose sum is σ = 261011964. Its totient is φ = 261011962.

The previous prime is 261011941. The next prime is 261012013. The reversal of 261011963 is 369110162.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 261011963 - 2¹² = 261007867 is a prime.

It is a super-2 number, since 2×261011963² = 136254489658226738, which contains 22 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (261011903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130505981 + 130505982.

It is an arithmetic number, because the mean of its divisors is an integer number (130505982).

Almost surely, 2^261011963 is an apocalyptic number.

261011963 is a deficient number, since it is larger than the sum of its proper divisors (1).

261011963 is an equidigital number, since it uses as much as digits as its factorization.

261011963 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1944, while the sum is 29.

The square root of 261011963 is about 16155.8646627161. The cubic root of 261011963 is about 639.0774166324.

The spelling of 261011963 in words is "two hundred sixty-one million, eleven thousand, nine hundred sixty-three".