61949716609 has 27 divisors (see below), whose sum is σ = 72388994083. Its totient is φ = 53005105120.

The previous prime is 61949716607. The next prime is 61949716637. The reversal of 61949716609 is 90661794916.

The square root of 61949716609 is 248897.

It is a perfect power (a square), and thus also a powerful number.

61949716609 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 48230748225 + 13718968384 = 219615^2 + 117128^2 .

It is not a de Polignac number, because 61949716609 - 2¹ = 61949716607 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61949716603) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 3644100969 + ... + 3644100985.

Almost surely, 2^61949716609 is an apocalyptic number.

61949716609 is the 248897-th square number.

61949716609 is the 124449-th centered octagonal number.

It is an amenable number.

61949716609 is a deficient number, since it is larger than the sum of its proper divisors (10439277474).

61949716609 is an frugal number, since it uses more digits than its factorization.

61949716609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122 (or 28 counting only the distinct ones).

The product of its (nonzero) digits is 4408992, while the sum is 58.

The spelling of 61949716609 in words is "sixty-one billion, nine hundred forty-nine million, seven hundred sixteen thousand, six hundred nine".