61501791808 has 56 divisors (see below), whose sum is σ = 126056404224. Its totient is φ = 29740761600.

The previous prime is 61501791787. The next prime is 61501791811. The reversal of 61501791808 is 80819710516.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 3584466 + ... + 3601582.

Almost surely, 2^61501791808 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 61501791808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (63028202112).

61501791808 is an abundant number, since it is smaller than the sum of its proper divisors (64554612416).

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

61501791808 is a wasteful number, since it uses less digits than its factorization.

61501791808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18971 (or 18961 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 46.

The spelling of 61501791808 in words is "sixty-one billion, five hundred one million, seven hundred ninety-one thousand, eight hundred eight".