1655005561 has 8 divisors (see below), whose sum is σ = 1824074784. Its totient is φ = 1489038720.

The previous prime is 1655005529. The next prime is 1655005567.

1655005561 is nontrivially palindromic in base 10.

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

It is a cyclic number.

It is not a de Polignac number, because 1655005561 - 2⁵ = 1655005529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1655005567) 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, 774475 + ... + 776608.

It is an arithmetic number, because the mean of its divisors is an integer number (228009348).

Almost surely, 2^1655005561 is an apocalyptic number.

1655005561 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1655005561 is a deficient number, since it is larger than the sum of its proper divisors (169069223).

1655005561 is a wasteful number, since it uses less digits than its factorization.

1655005561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1551191.

The product of its (nonzero) digits is 22500, while the sum is 34.

The square root of 1655005561 is about 40681.7595612579. The cubic root of 1655005561 is about 1182.8594734502.

The spelling of 1655005561 in words is "one billion, six hundred fifty-five million, five thousand, five hundred sixty-one".