61005491491 has 8 divisors (see below), whose sum is σ = 73821771360. Its totient is φ = 49214514048.

The previous prime is 61005491471. The next prime is 61005491501. The reversal of 61005491491 is 19419450016.

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

It is not a de Polignac number, because 61005491491 - 2⁹ = 61005490979 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61005491411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 256325476 + ... + 256325713.

It is an arithmetic number, because the mean of its divisors is an integer number (9227721420).

Almost surely, 2^61005491491 is an apocalyptic number.

61005491491 is a deficient number, since it is larger than the sum of its proper divisors (12816279869).

61005491491 is a wasteful number, since it uses less digits than its factorization.

61005491491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 512651213.

The product of its (nonzero) digits is 38880, while the sum is 40.

The spelling of 61005491491 in words is "sixty-one billion, five million, four hundred ninety-one thousand, four hundred ninety-one".