1653655561 has 4 divisors (see below), whose sum is σ = 1656970000. Its totient is φ = 1650341124.

The previous prime is 1653655559. The next prime is 1653655607. The reversal of 1653655561 is 1655563561.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1653655561 - 2¹ = 1653655559 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1653650561) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1656471 + ... + 1657468.

It is an arithmetic number, because the mean of its divisors is an integer number (414242500).

Almost surely, 2^1653655561 is an apocalyptic number.

It is an amenable number.

1653655561 is a deficient number, since it is larger than the sum of its proper divisors (3314439).

1653655561 is an equidigital number, since it uses as much as digits as its factorization.

1653655561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3314438.

The product of its digits is 405000, while the sum is 43.

The square root of 1653655561 is about 40665.1639736028. The cubic root of 1653655561 is about 1182.5377636196.

The spelling of 1653655561 in words is "one billion, six hundred fifty-three million, six hundred fifty-five thousand, five hundred sixty-one".