1656606561 has 8 divisors (see below), whose sum is σ = 2325061920. Its totient is φ = 1046277792.

The previous prime is 1656606559. The next prime is 1656606569. The reversal of 1656606561 is 1656066561.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1656606561 - 2¹ = 1656606559 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1656606569) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14531580 + ... + 14531693.

It is an arithmetic number, because the mean of its divisors is an integer number (290632740).

Almost surely, 2^1656606561 is an apocalyptic number.

It is an amenable number.

1656606561 is a deficient number, since it is larger than the sum of its proper divisors (668455359).

1656606561 is a wasteful number, since it uses less digits than its factorization.

1656606561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29063295.

The product of its (nonzero) digits is 194400, while the sum is 42.

The square root of 1656606561 is about 40701.4319281275. The cubic root of 1656606561 is about 1183.2407707976.

The spelling of 1656606561 in words is "one billion, six hundred fifty-six million, six hundred six thousand, five hundred sixty-one".