99767640 has 128 divisors (see below), whose sum is σ = 346959360. Its totient is φ = 22477824.

The previous prime is 99767621. The next prime is 99767653. The reversal of 99767640 is 4676799.

It is a self number, because there is not a number n which added to its sum of digits gives 99767640.

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, 60507 + ... + 62133.

It is an arithmetic number, because the mean of its divisors is an integer number (2710620).

Almost surely, 2^99767640 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 99767640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (173479680).

99767640 is an abundant number, since it is smaller than the sum of its proper divisors (247191720).

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

99767640 is a wasteful number, since it uses less digits than its factorization.

99767640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1721 (or 1717 counting only the distinct ones).

The product of its (nonzero) digits is 571536, while the sum is 48.

The square root of 99767640 is about 9988.3752432515. The cubic root of 99767640 is about 463.7990980244.

The spelling of 99767640 in words is "ninety-nine million, seven hundred sixty-seven thousand, six hundred forty".