11111555 has 16 divisors (see below), whose sum is σ = 16411584. Its totient is φ = 7032960.

The previous prime is 11111531. The next prime is 11111579. The reversal of 11111555 is 55511111.

It is an interprime number because it is at equal distance from previous prime (11111531) and next prime (11111579).

It is not a de Polignac number, because 11111555 - 2⁶ = 11111491 is a prime.

It is a nude number because it is divisible by every one of its digits.

It is a plaindrome in base 10.

It is a zygodrome in base 10.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11756 + ... + 12665.

It is an arithmetic number, because the mean of its divisors is an integer number (1025724).

Almost surely, 2^11111555 is an apocalyptic number.

11111555 is a deficient number, since it is larger than the sum of its proper divisors (5300029).

11111555 is a wasteful number, since it uses less digits than its factorization.

11111555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24446.

The product of its digits is 125, while the sum is 20.

The square root of 11111555 is about 3333.3999160017. The cubic root of 11111555 is about 223.1472881930.

Adding to 11111555 its reverse (55511111), we get a palindrome (66622666).

The spelling of 11111555 in words is "eleven million, one hundred eleven thousand, five hundred fifty-five".