61115515099 has 4 divisors (see below), whose sum is σ = 63086983360. Its totient is φ = 59144046840.

The previous prime is 61115515093. The next prime is 61115515127. The reversal of 61115515099 is 99051551116.

61115515099 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 cyclic number.

It is not a de Polignac number, because 61115515099 - 2⁵ = 61115515067 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61115515093) 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, 985734084 + ... + 985734145.

It is an arithmetic number, because the mean of its divisors is an integer number (15771745840).

Almost surely, 2^61115515099 is an apocalyptic number.

61115515099 is a deficient number, since it is larger than the sum of its proper divisors (1971468261).

61115515099 is a wasteful number, since it uses less digits than its factorization.

61115515099 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1971468260.

The product of its (nonzero) digits is 60750, while the sum is 43.

The spelling of 61115515099 in words is "sixty-one billion, one hundred fifteen million, five hundred fifteen thousand, ninety-nine".