2111555551 has 8 divisors (see below), whose sum is σ = 2414507040. Its totient is φ = 1808929248.

The previous prime is 2111555507. The next prime is 2111555561. The reversal of 2111555551 is 1555551112.

It is a happy number.

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

It is not a de Polignac number, because 2111555551 - 2¹³ = 2111547359 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 (2111555561) 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, 67216 + ... + 93493.

It is an arithmetic number, because the mean of its divisors is an integer number (301813380).

Almost surely, 2^2111555551 is an apocalyptic number.

2111555551 is a deficient number, since it is larger than the sum of its proper divisors (302951489).

2111555551 is a wasteful number, since it uses less digits than its factorization.

2111555551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162593.

The product of its digits is 6250, while the sum is 31.

The square root of 2111555551 is about 45951.6653778729. The cubic root of 2111555551 is about 1282.9237266046.

The spelling of 2111555551 in words is "two billion, one hundred eleven million, five hundred fifty-five thousand, five hundred fifty-one".