61111009 has 4 divisors (see below), whose sum is σ = 61521300. Its totient is φ = 60700720.

The previous prime is 61110997. The next prime is 61111019. The reversal of 61111009 is 90011116.

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

It can be written as a sum of positive squares in 2 ways, for example, as 13542400 + 47568609 = 3680^2 + 6897^2 .

It is a cyclic number.

It is not a de Polignac number, because 61111009 - 2¹⁷ = 60979937 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61111019) 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, 204922 + ... + 205219.

It is an arithmetic number, because the mean of its divisors is an integer number (15380325).

Almost surely, 2^61111009 is an apocalyptic number.

It is an amenable number.

61111009 is a deficient number, since it is larger than the sum of its proper divisors (410291).

61111009 is a wasteful number, since it uses less digits than its factorization.

61111009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 410290.

The product of its (nonzero) digits is 54, while the sum is 19.

The square root of 61111009 is about 7817.3530686544. The cubic root of 61111009 is about 393.8883641050. Note that the first 3 decimals are identical.

The spelling of 61111009 in words is "sixty-one million, one hundred eleven thousand, nine".