2051555111 has 8 divisors (see below), whose sum is σ = 2124533664. Its totient is φ = 1979845920.

The previous prime is 2051555101. The next prime is 2051555113. The reversal of 2051555111 is 1115551502.

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 2051555111 - 2⁶ = 2051555047 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2051555113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 314051 + ... + 320516.

It is an arithmetic number, because the mean of its divisors is an integer number (265566708).

Almost surely, 2^2051555111 is an apocalyptic number.

2051555111 is a deficient number, since it is larger than the sum of its proper divisors (72978553).

2051555111 is an equidigital number, since it uses as much as digits as its factorization.

2051555111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 634681.

The product of its (nonzero) digits is 1250, while the sum is 26.

The square root of 2051555111 is about 45294.0957631345. The cubic root of 2051555111 is about 1270.6552328045.

The spelling of 2051555111 in words is "two billion, fifty-one million, five hundred fifty-five thousand, one hundred eleven".