111561641 has 4 divisors (see below), whose sum is σ = 111638352. Its totient is φ = 111484932.

The previous prime is 111561631. The next prime is 111561649. The reversal of 111561641 is 146165111.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 111561641 - 2⁶ = 111561577 is a prime.

It is a super-2 number, since 2×111561641² = 24891999485225762, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 111561641.

It is not an unprimeable number, because it can be changed into a prime (111561649) 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, 36131 + ... + 39096.

It is an arithmetic number, because the mean of its divisors is an integer number (27909588).

Almost surely, 2^111561641 is an apocalyptic number.

It is an amenable number.

111561641 is a deficient number, since it is larger than the sum of its proper divisors (76711).

111561641 is an equidigital number, since it uses as much as digits as its factorization.

111561641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76710.

The product of its digits is 720, while the sum is 26.

The square root of 111561641 is about 10562.2744236268. The cubic root of 111561641 is about 481.3987570496.

The spelling of 111561641 in words is "one hundred eleven million, five hundred sixty-one thousand, six hundred forty-one".