261907487 has 2 divisors, whose sum is σ = 261907488. Its totient is φ = 261907486.

The previous prime is 261907361. The next prime is 261907493. The reversal of 261907487 is 784709162.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 261907487 - 2⁸ = 261907231 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261927487) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130953743 + 130953744.

It is an arithmetic number, because the mean of its divisors is an integer number (130953744).

Almost surely, 2^261907487 is an apocalyptic number.

261907487 is a deficient number, since it is larger than the sum of its proper divisors (1).

261907487 is an equidigital number, since it uses as much as digits as its factorization.

261907487 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 169344, while the sum is 44.

The square root of 261907487 is about 16183.5560678115. The cubic root of 261907487 is about 639.8074673136.

The spelling of 261907487 in words is "two hundred sixty-one million, nine hundred seven thousand, four hundred eighty-seven".