61491711798 has 24 divisors (see below), whose sum is σ = 145344046536. Its totient is φ = 18633852000.

The previous prime is 61491711791. The next prime is 61491711899. The reversal of 61491711798 is 89711719416.

61491711798 is a `hidden beast` number, since 61 + 491 + 7 + 1 + 1 + 7 + 98 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61491711791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 155281903 + ... + 155282298.

It is an arithmetic number, because the mean of its divisors is an integer number (6056001939).

Almost surely, 2^61491711798 is an apocalyptic number.

61491711798 is an abundant number, since it is smaller than the sum of its proper divisors (83852334738).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61491711798 is a wasteful number, since it uses less digits than its factorization.

61491711798 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 310564220 (or 310564217 counting only the distinct ones).

The product of its digits is 762048, while the sum is 54.

The spelling of 61491711798 in words is "sixty-one billion, four hundred ninety-one million, seven hundred eleven thousand, seven hundred ninety-eight".