661341047 has 2 divisors, whose sum is σ = 661341048. Its totient is φ = 661341046.

The previous prime is 661341019. The next prime is 661341127. The reversal of 661341047 is 740143166.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 661341047 - 2⁶ = 661340983 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (661341347) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330670523 + 330670524.

It is an arithmetic number, because the mean of its divisors is an integer number (330670524).

Almost surely, 2^661341047 is an apocalyptic number.

661341047 is a deficient number, since it is larger than the sum of its proper divisors (1).

661341047 is an equidigital number, since it uses as much as digits as its factorization.

661341047 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12096, while the sum is 32.

The square root of 661341047 is about 25716.5520044970. The cubic root of 661341047 is about 871.2480642761.

The spelling of 661341047 in words is "six hundred sixty-one million, three hundred forty-one thousand, forty-seven".