111561640 has 32 divisors (see below), whose sum is σ = 253610280. Its totient is φ = 44163072.

The previous prime is 111561631. The next prime is 111561649. The reversal of 111561640 is 46165111.

It is an interprime number because it is at equal distance from previous prime (111561631) and next prime (111561649).

It can be written as a sum of positive squares in 4 ways, for example, as 105637284 + 5924356 = 10278^2 + 2434^2 .

It is not an unprimeable number, because it can be changed into a prime (111561649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10497 + ... + 18256.

Almost surely, 2^111561640 is an apocalyptic number.

111561640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

111561640 is an abundant number, since it is smaller than the sum of its proper divisors (142048640).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

111561640 is a wasteful number, since it uses less digits than its factorization.

111561640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28861 (or 28857 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 25.

The square root of 111561640 is about 10562.2743762885. The cubic root of 111561640 is about 481.3987556112.

It can be divided in two parts, 11 and 1561640, that added together give a palindrome (1561651).

The spelling of 111561640 in words is "one hundred eleven million, five hundred sixty-one thousand, six hundred forty".