61547045809 has 2 divisors, whose sum is σ = 61547045810. Its totient is φ = 61547045808.

The previous prime is 61547045797. The next prime is 61547045851. The reversal of 61547045809 is 90854074516.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 35473839025 + 26073206784 = 188345^2 + 161472^2 .

It is a cyclic number.

It is not a de Polignac number, because 61547045809 - 2³³ = 52957111217 is a prime.

It is not a weakly prime, because it can be changed into another prime (61547045869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30773522904 + 30773522905.

It is an arithmetic number, because the mean of its divisors is an integer number (30773522905).

Almost surely, 2^61547045809 is an apocalyptic number.

It is an amenable number.

61547045809 is a deficient number, since it is larger than the sum of its proper divisors (1).

61547045809 is an equidigital number, since it uses as much as digits as its factorization.

61547045809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1209600, while the sum is 49.

The spelling of 61547045809 in words is "sixty-one billion, five hundred forty-seven million, forty-five thousand, eight hundred nine".