261854947 has 2 divisors, whose sum is σ = 261854948. Its totient is φ = 261854946.

The previous prime is 261854911. The next prime is 261854969. The reversal of 261854947 is 749458162.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 261854947 - 2⁷ = 261854819 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 261854897 and 261854906.

It is not a weakly prime, because it can be changed into another prime (261854147) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130927473 + 130927474.

It is an arithmetic number, because the mean of its divisors is an integer number (130927474).

Almost surely, 2^261854947 is an apocalyptic number.

261854947 is a deficient number, since it is larger than the sum of its proper divisors (1).

261854947 is an equidigital number, since it uses as much as digits as its factorization.

261854947 is an evil number, because the sum of its binary digits is even.

The product of its digits is 483840, while the sum is 46.

The square root of 261854947 is about 16181.9327337621. The cubic root of 261854947 is about 639.7646815539.

The spelling of 261854947 in words is "two hundred sixty-one million, eight hundred fifty-four thousand, nine hundred forty-seven".