99999977 has 16 divisors (see below), whose sum is σ = 126185472. Its totient is φ = 76978320.

The previous prime is 99999971. The next prime is 99999989. The reversal of 99999977 is 77999999.

It is a cyclic number.

It is not a de Polignac number, because 99999977 - 2⁸ = 99999721 is a prime.

It is a nialpdrome in base 10.

It is a zygodrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (99999971) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1433 + ... + 14214.

It is an arithmetic number, because the mean of its divisors is an integer number (7886592).

Almost surely, 2^99999977 is an apocalyptic number.

It is an amenable number.

99999977 is a deficient number, since it is larger than the sum of its proper divisors (26185495).

99999977 is a wasteful number, since it uses less digits than its factorization.

99999977 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15748.

The product of its digits is 26040609, while the sum is 68.

The square root of 99999977 is about 9999.9988499999. The cubic root of 99999977 is about 464.1588477758.

The spelling of 99999977 in words is "ninety-nine million, nine hundred ninety-nine thousand, nine hundred seventy-seven".