111957581 has 2 divisors, whose sum is σ = 111957582. Its totient is φ = 111957580.

The previous prime is 111957577. The next prime is 111957589. The reversal of 111957581 is 185759111.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 106708900 + 5248681 = 10330^2 + 2291^2 .

It is a cyclic number.

It is not a de Polignac number, because 111957581 - 2² = 111957577 is a prime.

It is a super-2 number, since 2×111957581² = 25068999886743122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (111957589) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55978790 + 55978791.

It is an arithmetic number, because the mean of its divisors is an integer number (55978791).

Almost surely, 2^111957581 is an apocalyptic number.

It is an amenable number.

111957581 is a deficient number, since it is larger than the sum of its proper divisors (1).

111957581 is an equidigital number, since it uses as much as digits as its factorization.

111957581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12600, while the sum is 38.

The square root of 111957581 is about 10581.0009450902. Note that the first 3 decimals coincide. The cubic root of 111957581 is about 481.9675904931.

The spelling of 111957581 in words is "one hundred eleven million, nine hundred fifty-seven thousand, five hundred eighty-one".