261380407 has 2 divisors, whose sum is σ = 261380408. Its totient is φ = 261380406.

The previous prime is 261380401. The next prime is 261380417. The reversal of 261380407 is 704083162.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 261380407 - 2¹⁹ = 260856119 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261380401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130690203 + 130690204.

It is an arithmetic number, because the mean of its divisors is an integer number (130690204).

Almost surely, 2^261380407 is an apocalyptic number.

261380407 is a deficient number, since it is larger than the sum of its proper divisors (1).

261380407 is an equidigital number, since it uses as much as digits as its factorization.

261380407 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8064, while the sum is 31.

The square root of 261380407 is about 16167.2634357210. The cubic root of 261380407 is about 639.3779820806.

The spelling of 261380407 in words is "two hundred sixty-one million, three hundred eighty thousand, four hundred seven".