61916816640 has 288 divisors, whose sum is σ = 229186492416. Its totient is φ = 13952655360.

The previous prime is 61916816587. The next prime is 61916816657. The reversal of 61916816640 is 4661861916.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 61916816640.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1892259 + ... + 1924701.

It is an arithmetic number, because the mean of its divisors is an integer number (795786432).

Almost surely, 2^61916816640 is an apocalyptic number.

61916816640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61916816640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (114593246208).

61916816640 is an abundant number, since it is smaller than the sum of its proper divisors (167269675776).

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

61916816640 is a wasteful number, since it uses less digits than its factorization.

61916816640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32545 (or 32531 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 48.

The spelling of 61916816640 in words is "sixty-one billion, nine hundred sixteen million, eight hundred sixteen thousand, six hundred forty".