111315551 has 4 divisors (see below), whose sum is σ = 112463232. Its totient is φ = 110167872.

The previous prime is 111315511. The next prime is 111315563. The reversal of 111315551 is 155513111.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-111315551 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 (111315511) 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, 573695 + ... + 573888.

It is an arithmetic number, because the mean of its divisors is an integer number (28115808).

Almost surely, 2^111315551 is an apocalyptic number.

111315551 is a deficient number, since it is larger than the sum of its proper divisors (1147681).

111315551 is an equidigital number, since it uses as much as digits as its factorization.

111315551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1147680.

The product of its digits is 375, while the sum is 23.

The square root of 111315551 is about 10550.6185126750. The cubic root of 111315551 is about 481.0445294563.

Adding to 111315551 its reverse (155513111), we get a palindrome (266828662).

The spelling of 111315551 in words is "one hundred eleven million, three hundred fifteen thousand, five hundred fifty-one".