61809906798 has 24 divisors (see below), whose sum is σ = 135302102208. Its totient is φ = 20390896512.

The previous prime is 61809906779. The next prime is 61809906833. The reversal of 61809906798 is 89760990816.

61809906798 is a `hidden beast` number, since 618 + 0 + 9 + 9 + 0 + 6 + 7 + 9 + 8 = 666.

It is a super-2 number, since 2×61809906798² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17698686 + ... + 17702177.

It is an arithmetic number, because the mean of its divisors is an integer number (5637587592).

Almost surely, 2^61809906798 is an apocalyptic number.

61809906798 is an abundant number, since it is smaller than the sum of its proper divisors (73492195410).

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

61809906798 is a wasteful number, since it uses less digits than its factorization.

61809906798 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35400968 (or 35400965 counting only the distinct ones).

The product of its (nonzero) digits is 11757312, while the sum is 63.

The spelling of 61809906798 in words is "sixty-one billion, eight hundred nine million, nine hundred six thousand, seven hundred ninety-eight".