61778236416 has 352 divisors, whose sum is σ = 184878489600. Its totient is φ = 18212290560.

The previous prime is 61778236379. The next prime is 61778236511. The reversal of 61778236416 is 61463287716.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 172084045 + ... + 172084403.

Almost surely, 2^61778236416 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 61778236416, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (92439244800).

61778236416 is an abundant number, since it is smaller than the sum of its proper divisors (123100253184).

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

61778236416 is a wasteful number, since it uses less digits than its factorization.

61778236416 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 565 (or 547 counting only the distinct ones).

The product of its digits is 2032128, while the sum is 51.

The spelling of 61778236416 in words is "sixty-one billion, seven hundred seventy-eight million, two hundred thirty-six thousand, four hundred sixteen".