99777840 has 80 divisors (see below), whose sum is σ = 319312896. Its totient is φ = 25747200.

The previous prime is 99777833. The next prime is 99777857. The reversal of 99777840 is 4877799.

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 735 + ... + 14145.

Almost surely, 2^99777840 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 99777840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (159656448).

99777840 is an abundant number, since it is smaller than the sum of its proper divisors (219535056).

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

99777840 is a wasteful number, since it uses less digits than its factorization.

99777840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13458 (or 13452 counting only the distinct ones).

The product of its (nonzero) digits is 889056, while the sum is 51.

The square root of 99777840 is about 9988.8858237543. The cubic root of 99777840 is about 463.8149033816.

The spelling of 99777840 in words is "ninety-nine million, seven hundred seventy-seven thousand, eight hundred forty".