99977640 has 160 divisors (see below), whose sum is σ = 350909280. Its totient is φ = 22786176.

The previous prime is 99977627. The next prime is 99977641. The reversal of 99977640 is 4677999.

It is a nialpdrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (99977641) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 287947 + ... + 288293.

It is an arithmetic number, because the mean of its divisors is an integer number (2193183).

Almost surely, 2^99977640 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 99977640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (175454640).

99977640 is an abundant number, since it is smaller than the sum of its proper divisors (250931640).

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

99977640 is a wasteful number, since it uses less digits than its factorization.

99977640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 389 (or 364 counting only the distinct ones).

The product of its (nonzero) digits is 857304, while the sum is 51.

The square root of 99977640 is about 9998.8819374968. The cubic root of 99977640 is about 464.1242854737.

The spelling of 99977640 in words is "ninety-nine million, nine hundred seventy-seven thousand, six hundred forty".