61819770408 has 128 divisors (see below), whose sum is σ = 172380856320. Its totient is φ = 18314005760.

The previous prime is 61819770407. The next prime is 61819770431. The reversal of 61819770408 is 80407791816.

It is not an unprimeable number, because it can be changed into a prime (61819770401) 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 31 ways as a sum of consecutive naturals, for example, 13683766 + ... + 13688282.

It is an arithmetic number, because the mean of its divisors is an integer number (1346725440).

Almost surely, 2^61819770408 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61819770408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86190428160).

61819770408 is an abundant number, since it is smaller than the sum of its proper divisors (110561085912).

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

61819770408 is a wasteful number, since it uses less digits than its factorization.

61819770408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5687 (or 5683 counting only the distinct ones).

The product of its (nonzero) digits is 677376, while the sum is 51.

The spelling of 61819770408 in words is "sixty-one billion, eight hundred nineteen million, seven hundred seventy thousand, four hundred eight".