1660406163561 has 48 divisors (see below), whose sum is σ = 2465400921984. Its totient is φ = 1076243680512.

The previous prime is 1660406163547. The next prime is 1660406163569. The reversal of 1660406163561 is 1653616040661.

1660406163561 is a `hidden beast` number, since 1 + 6 + 6 + 0 + 4 + 0 + 6 + 1 + 635 + 6 + 1 = 666.

It is not a de Polignac number, because 1660406163561 - 2²³ = 1660397774953 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1660406163569) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 89178325 + ... + 89196941.

It is an arithmetic number, because the mean of its divisors is an integer number (51362519208).

Almost surely, 2^{1660406163561} is an apocalyptic number.

It is an amenable number.

1660406163561 is a deficient number, since it is larger than the sum of its proper divisors (804994758423).

1660406163561 is a wasteful number, since it uses less digits than its factorization.

1660406163561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19710 (or 19707 counting only the distinct ones).

The product of its (nonzero) digits is 466560, while the sum is 45.

The spelling of 1660406163561 in words is "one trillion, six hundred sixty billion, four hundred six million, one hundred sixty-three thousand, five hundred sixty-one".