61518917 has 4 divisors (see below), whose sum is σ = 61669740. Its totient is φ = 61368096.

The previous prime is 61518907. The next prime is 61518923. The reversal of 61518917 is 71981516.

61518917 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 can be written as a sum of positive squares in 2 ways, for example, as 55338721 + 6180196 = 7439^2 + 2486^2 .

It is a cyclic number.

It is not a de Polignac number, because 61518917 - 2²² = 57324613 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61518907) 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 3 ways as a sum of consecutive naturals, for example, 74798 + ... + 75615.

It is an arithmetic number, because the mean of its divisors is an integer number (15417435).

Almost surely, 2^61518917 is an apocalyptic number.

It is an amenable number.

61518917 is a deficient number, since it is larger than the sum of its proper divisors (150823).

61518917 is a wasteful number, since it uses less digits than its factorization.

61518917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 150822.

The product of its digits is 15120, while the sum is 38.

The square root of 61518917 is about 7843.3995818140. The cubic root of 61518917 is about 394.7628058409.

The spelling of 61518917 in words is "sixty-one million, five hundred eighteen thousand, nine hundred seventeen".