261045979 has 2 divisors, whose sum is σ = 261045980. Its totient is φ = 261045978.

The previous prime is 261045973. The next prime is 261046007. The reversal of 261045979 is 979540162.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 261045979 - 2¹¹ = 261043931 is a prime.

It is equal to p_14249896 and since 261045979 and 14249896 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (261045973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130522989 + 130522990.

It is an arithmetic number, because the mean of its divisors is an integer number (130522990).

Almost surely, 2^261045979 is an apocalyptic number.

261045979 is a deficient number, since it is larger than the sum of its proper divisors (1).

261045979 is an equidigital number, since it uses as much as digits as its factorization.

261045979 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 136080, while the sum is 43.

The square root of 261045979 is about 16156.9173730635. The cubic root of 261045979 is about 639.1051777011.

The spelling of 261045979 in words is "two hundred sixty-one million, forty-five thousand, nine hundred seventy-nine".