2660621555 has 8 divisors (see below), whose sum is σ = 3193233792. Its totient is φ = 2128171968.

The previous prime is 2660621549. The next prime is 2660621581. The reversal of 2660621555 is 5551260662.

It is a happy number.

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 2660621555 - 2⁴ = 2660621539 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1187 + ... + 72956.

It is an arithmetic number, because the mean of its divisors is an integer number (399154224).

Almost surely, 2^2660621555 is an apocalyptic number.

2660621555 is a deficient number, since it is larger than the sum of its proper divisors (532612237).

2660621555 is an equidigital number, since it uses as much as digits as its factorization.

2660621555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81325.

The product of its (nonzero) digits is 108000, while the sum is 38.

The square root of 2660621555 is about 51581.2131982178. The cubic root of 2660621555 is about 1385.6738943153.

The spelling of 2660621555 in words is "two billion, six hundred sixty million, six hundred twenty-one thousand, five hundred fifty-five".