61720649499 has 8 divisors (see below), whose sum is σ = 82663232512. Its totient is φ = 40962583080.

The previous prime is 61720649491. The next prime is 61720649509. The reversal of 61720649499 is 99494602716.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 61720649499 - 2³ = 61720649491 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61720649491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 46128367 + ... + 46129704.

It is an arithmetic number, because the mean of its divisors is an integer number (10332904064).

Almost surely, 2^61720649499 is an apocalyptic number.

61720649499 is a deficient number, since it is larger than the sum of its proper divisors (20942583013).

61720649499 is a wasteful number, since it uses less digits than its factorization.

61720649499 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92258297.

The product of its (nonzero) digits is 5878656, while the sum is 57.

The spelling of 61720649499 in words is "sixty-one billion, seven hundred twenty million, six hundred forty-nine thousand, four hundred ninety-nine".