2013555561 has 4 divisors (see below), whose sum is σ = 2684740752. Its totient is φ = 1342370372.

The previous prime is 2013555541. The next prime is 2013555563. The reversal of 2013555561 is 1655553102.

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 2013555561 - 2⁷ = 2013555433 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2013555563) 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, 335592591 + ... + 335592596.

It is an arithmetic number, because the mean of its divisors is an integer number (671185188).

Almost surely, 2^2013555561 is an apocalyptic number.

It is an amenable number.

2013555561 is a deficient number, since it is larger than the sum of its proper divisors (671185191).

2013555561 is an equidigital number, since it uses as much as digits as its factorization.

2013555561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 671185190.

The product of its (nonzero) digits is 22500, while the sum is 33.

The square root of 2013555561 is about 44872.6593929979. The cubic root of 2013555561 is about 1262.7611324823.

The spelling of 2013555561 in words is "two billion, thirteen million, five hundred fifty-five thousand, five hundred sixty-one".