661560047 has 2 divisors, whose sum is σ = 661560048. Its totient is φ = 661560046.

The previous prime is 661560043. The next prime is 661560071. The reversal of 661560047 is 740065166.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 661560047 - 2² = 661560043 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 661559989 and 661560016.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (661560043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330780023 + 330780024.

It is an arithmetic number, because the mean of its divisors is an integer number (330780024).

Almost surely, 2^661560047 is an apocalyptic number.

661560047 is a deficient number, since it is larger than the sum of its proper divisors (1).

661560047 is an equidigital number, since it uses as much as digits as its factorization.

661560047 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 30240, while the sum is 35.

The square root of 661560047 is about 25720.8096101192. The cubic root of 661560047 is about 871.3442235722.

The spelling of 661560047 in words is "six hundred sixty-one million, five hundred sixty thousand, forty-seven".