261904939 has 2 divisors, whose sum is σ = 261904940. Its totient is φ = 261904938.

The previous prime is 261904927. The next prime is 261904961. The reversal of 261904939 is 939409162.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 261904939 - 2¹¹ = 261902891 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 261904895 and 261904904.

It is not a weakly prime, because it can be changed into another prime (261904919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130952469 + 130952470.

It is an arithmetic number, because the mean of its divisors is an integer number (130952470).

Almost surely, 2^261904939 is an apocalyptic number.

261904939 is a deficient number, since it is larger than the sum of its proper divisors (1).

261904939 is an equidigital number, since it uses as much as digits as its factorization.

261904939 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 104976, while the sum is 43.

The square root of 261904939 is about 16183.4773457375. The cubic root of 261904939 is about 639.8053924910.

The spelling of 261904939 in words is "two hundred sixty-one million, nine hundred four thousand, nine hundred thirty-nine".