261423947 has 2 divisors, whose sum is σ = 261423948. Its totient is φ = 261423946.

The previous prime is 261423889. The next prime is 261423973. The reversal of 261423947 is 749324162.

261423947 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 261423947 - 2⁸ = 261423691 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 261423947.

It is not a weakly prime, because it can be changed into another prime (261423647) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130711973 + 130711974.

It is an arithmetic number, because the mean of its divisors is an integer number (130711974).

Almost surely, 2^261423947 is an apocalyptic number.

261423947 is a deficient number, since it is larger than the sum of its proper divisors (1).

261423947 is an equidigital number, since it uses as much as digits as its factorization.

261423947 is an evil number, because the sum of its binary digits is even.

The product of its digits is 72576, while the sum is 38.

The square root of 261423947 is about 16168.6099278819. The cubic root of 261423947 is about 639.4134820275.

The spelling of 261423947 in words is "two hundred sixty-one million, four hundred twenty-three thousand, nine hundred forty-seven".