61115566 has 4 divisors (see below), whose sum is σ = 91673352. Its totient is φ = 30557782.

The previous prime is 61115521. The next prime is 61115567. The reversal of 61115566 is 66551116.

61115566 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a super-2 number, since 2×61115566² = 7470224815000712, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61115567) 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 as a sum of consecutive naturals, namely, 15278890 + ... + 15278893.

It is an arithmetic number, because the mean of its divisors is an integer number (22918338).

Almost surely, 2^61115566 is an apocalyptic number.

61115566 is a deficient number, since it is larger than the sum of its proper divisors (30557786).

61115566 is a wasteful number, since it uses less digits than its factorization.

61115566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30557785.

The product of its digits is 5400, while the sum is 31.

The square root of 61115566 is about 7817.6445301638. The cubic root of 61115566 is about 393.8981545105.

The spelling of 61115566 in words is "sixty-one million, one hundred fifteen thousand, five hundred sixty-six".